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A defensive wall is a
fortification A fortification is a military construction or building designed for the defense of territories in warfare, and is also used to establish rule in a region during peacetime. The term is derived from Latin ''fortis'' ("strong") and ''facere'' ...
usually used to protect a city, town or other settlement from potential aggressors. The walls can range from simple palisades or earthworks to extensive military fortifications with towers, bastions and gates for access to the city. From ancient to modern times, they were used to enclose settlements. Generally, these are referred to as city walls or town walls, although there were also walls, such as the
Great Wall of China The Great Wall of China (, literally "ten thousand ''li'' wall") is a series of fortifications that were built across the historical northern borders of ancient Chinese states and Imperial China as protection against various nomadic grou ...
,
Walls of Benin The Walls of Benin are a series of earthworks made up of banks and ditches, called ''ya'' in the Edo language, in the area around present-day Benin City, the capital of present-day Edo, Nigeria. They consist of of city iya and an estimated o ...
,
Hadrian's Wall Hadrian's Wall ( la, Vallum Aelium), also known as the Roman Wall, Picts' Wall, or ''Vallum Hadriani'' in Latin, is a former defensive fortification of the Roman province of Britannia, begun in AD 122 in the reign of the Emperor Hadrian. R ...
, Anastasian Wall, and the Atlantic Wall, which extended far beyond the borders of a city and were used to enclose regions or mark territorial boundaries. In mountainous terrain, defensive walls such as ''
letzi A ''Letzi'' (plural: ''Letzinen'', also known in German as a ''Talsperre'' in the sense of a fortification, not a dam) or ''Letzimauer'' refers to defensive barriers whose purpose is to protect the entrance into a valley. The term is Swiss, and ...
s'' were used in combination with castles to seal valleys from potential attack. Beyond their defensive utility, many walls also had important symbolic functions representing the status and independence of the communities they embraced. Existing ancient walls are almost always
masonry Masonry is the building of structures from individual units, which are often laid in and bound together by mortar; the term ''masonry'' can also refer to the units themselves. The common materials of masonry construction are bricks, building ...
structures, although brick and timber-built variants are also known. Depending on the
topography Topography is the study of the forms and features of land surfaces. The topography of an area may refer to the land forms and features themselves, or a description or depiction in maps. Topography is a field of geoscience and planetary sci ...
of the area surrounding the city or the settlement the wall is intended to protect, elements of the terrain such as rivers or coastlines may be incorporated in order to make the wall more effective. Walls may only be crossed by entering the appropriate
city gate A city gate is a gate which is, or was, set within a city wall. It is a type of fortified gateway. Uses City gates were traditionally built to provide a point of controlled access to and departure from a walled city for people, vehicles, goods ...
and are often supplemented with towers. The practice of building these massive walls, though having its origins in prehistory, was refined during the rise of
city-state A city-state is an independent sovereign city which serves as the center of political, economic, and cultural life over its contiguous territory. They have existed in many parts of the world since the dawn of history, including cities such as ...
s, and energetic wall-building continued into the medieval period and beyond in certain parts of Europe. Simpler defensive walls of earth or stone, thrown up around
hillfort A hillfort is a type of earthwork used as a fortified refuge or defended settlement, located to exploit a rise in elevation for defensive advantage. They are typically European and of the Bronze Age or Iron Age. Some were used in the post-Roma ...
s,
ringwork A ringwork is a form of fortified defensive structure, usually circular or oval in shape. Ringworks are essentially motte-and-bailey castles without the motte. Defences were usually earthworks in the form of a ditch and bank surrounding the sit ...
s, early
castle A castle is a type of fortified structure built during the Middle Ages predominantly by the nobility or royalty and by military orders. Scholars debate the scope of the word ''castle'', but usually consider it to be the private fortified r ...
s and the like, tend to be referred to as ramparts or banks.


History


Mesopotamia

From very early history to modern times, walls have been a near necessity for every city.
Uruk Uruk, also known as Warka or Warkah, was an ancient city of Sumer (and later of Babylonia) situated east of the present bed of the Euphrates River on the dried-up ancient channel of the Euphrates east of modern Samawah, Al-Muthannā, Iraq.Harm ...
in ancient
Sumer Sumer () is the earliest known civilization in the historical region of southern Mesopotamia (south-central Iraq), emerging during the Chalcolithic and early Bronze Ages between the sixth and fifth millennium BC. It is one of the cradles of c ...
(
Mesopotamia Mesopotamia ''Mesopotamíā''; ar, بِلَاد ٱلرَّافِدَيْن or ; syc, ܐܪܡ ܢܗܪ̈ܝܢ, or , ) is a historical region of Western Asia situated within the Tigris–Euphrates river system, in the northern part of the F ...
) is one of the world's oldest known walled cities. Before that, the
proto-city A proto-city is a large, dense Neolithic settlement that is largely distinguished from a city by its lack of planning and centralized rule. While the precise classification of many sites considered proto-cities is ambiguous and subject to consid ...
of
Jericho Jericho ( ; ar, أريحا ; he, יְרִיחוֹ ) is a Palestinian city in the West Bank. It is located in the Jordan Valley, with the Jordan River to the east and Jerusalem to the west. It is the administrative seat of the Jericho Gove ...
in the
West Bank The West Bank ( ar, الضفة الغربية, translit=aḍ-Ḍiffah al-Ġarbiyyah; he, הגדה המערבית, translit=HaGadah HaMaʽaravit, also referred to by some Israelis as ) is a landlocked territory near the coast of the Mediter ...
had a wall surrounding it as early as the 8th millenniumBC. The earliest known town wall in Europe is of
Solnitsata Solnitsata ( bg, Солницата, "The Saltworks") was a prehistoric town located in present-day Bulgaria, near the modern city of Provadia. Believed by archaeologists to be the oldest town in Europe, Solnitsata was a fortified stone settlement ...
, built in the 6th or 5th millennium BC. The Assyrians deployed large labour forces to build new palaces, temples and defensive walls.
Babylon ''Bābili(m)'' * sux, 𒆍𒀭𒊏𒆠 * arc, 𐡁𐡁𐡋 ''Bāḇel'' * syc, ܒܒܠ ''Bāḇel'' * grc-gre, Βαβυλών ''Babylṓn'' * he, בָּבֶל ''Bāvel'' * peo, 𐎲𐎠𐎲𐎡𐎽𐎢 ''Bābiru'' * elx, 𒀸𒁀𒉿𒇷 ''Babi ...
was one of the most famous cities of the ancient world, especially as a result of the building program of Nebuchadnezzar, who expanded the walls and built the
Ishtar Gate The Ishtar Gate was the eighth gate to the inner city of Babylon (in the area of present-day Hillah, Babil Governorate, Iraq). It was constructed circa 575 BCE by order of King Nebuchadnezzar II on the north side of the city. It was part ...
. The Persians built
defensive walls A defensive wall is a fortification usually used to protect a city, town or other settlement from potential aggressors. The walls can range from simple palisades or earthworks to extensive military fortifications with towers, bastions and gates ...
to protect their territories, notably the Derbent Wall and the
Great Wall of Gorgan The Great Wall of Gorgan is a Sasanian-era defense system located near modern Gorgan in the Golestān Province of northeastern Iran, at the southeastern corner of the Caspian Sea. The western, Caspian Sea, end of the wall is near the remains ...
built on the either sides of the
Caspian Sea The Caspian Sea is the world's largest inland body of water, often described as the world's largest lake or a full-fledged sea. An endorheic basin, it lies between Europe and Asia; east of the Caucasus, west of the broad steppe of Central Asia ...
against nomadic nations.


South Asia

Some settlements in the
Indus Valley civilization The Indus Valley Civilisation (IVC), also known as the Indus Civilisation was a Bronze Age civilisation in the northwestern regions of South Asia, lasting from 3300 BCE to 1300 BCE, and in its mature form 2600 BCE to 1900&n ...
were also fortified. By about 3500BC, hundreds of small farming villages dotted the
Indus The Indus ( ) is a transboundary river of Asia and a trans-Himalayan river of South and Central Asia. The river rises in mountain springs northeast of Mount Kailash in Western Tibet, flows northwest through the disputed region of Kashmir, ...
floodplain. Many of these settlements had fortifications and planned streets. The stone and mud brick houses of
Kot Diji The ancient site at Kot Diji ( sd, ڪوٽ ڏیجي; ur, کوٹ ڈیجی) was the forerunner of the Indus Civilization. The occupation of this site is attested already at 3300 BCE. The remains consist of two parts; the citadel area on high ground ...
were clustered behind massive stone flood dykes and defensive walls, for neighboring communities quarreled constantly about the control of prime agricultural land.
Mundigak Mundigak ( ps, منډیګک) is an archaeological site in Kandahar province in Afghanistan Afghanistan, officially the Islamic Emirate of Afghanistan,; prs, امارت اسلامی افغانستان is a landlocked country located at ...
(c. 2500BC) in present-day south-east
Afghanistan Afghanistan, officially the Islamic Emirate of Afghanistan,; prs, امارت اسلامی افغانستان is a landlocked country located at the crossroads of Central Asia and South Asia. Referred to as the Heart of Asia, it is bordere ...
has defensive walls and square bastions of sun dried bricks.


Southeast Asia

The concept of a city fully enclosed by walls was not fully developed in Southeast Asia until the arrival of Europeans. However, Burma serves an exception, as they had a longer tradition of fortified walled towns; towns in Burma had city walls by 1566. Besides that, Rangoon in 1755 had stockades made of teak logs on a ground
rampart Rampart may refer to: * Rampart (fortification), a defensive wall or bank around a castle, fort or settlement Rampart may also refer to: * "O'er the Ramparts We Watched" is a key line from "The Star-Spangled Banner", the national anthem of the ...
. The city was fortified with six city gates with each gate flanked by massive brick towers. In other areas of Southeast Asia, city walls spread in the 16th and 17th century along with the rapid growth of cities in this period as a need to defend against European naval attack.
Ayutthaya Ayutthaya, Ayudhya, or Ayuthia may refer to: * Ayutthaya Kingdom, a Thai kingdom that existed from 1350 to 1767 ** Ayutthaya Historical Park, the ruins of the old capital city of the Ayutthaya Kingdom * Phra Nakhon Si Ayutthaya province (locally ...
built its walls in 1550 and
Banten Banten ( id, Banten; Sundanese: , romanized ''Banten'') is the westernmost province on the island of Java, Indonesia. Its capital city is Serang. The province borders West Java and the Special Capital Region of Jakarta on the east, the Ja ...
,
Jepara Jepara is a town in the province of Central Java, Indonesia. Jepara is on the north coast of Java, north-east of Semarang, not far from Mount Muria, with a population of 92,967 in mid 2019. It is also the main town of Jepara Regency, which has a ...
,
Tuban Tuban is a town located on the north coast of Java, in Tuban Regency (of which the town is the administrative capital), approximately west of Surabaya, the capital of East Java. Tuban Regency is surrounded by Lamongan Regency in the east, Bo ...
and
Surabaya Surabaya ( jv, ꦱꦸꦫꦧꦪ or jv, ꦯꦹꦫꦨꦪ; ; ) is the capital city of the Provinces of Indonesia, Indonesian province of East Java and the List of Indonesian cities by population, second-largest city in Indonesia, after Jakarta. L ...
all had theirs by 1600; while
Makassar Makassar (, mak, ᨆᨀᨔᨑ, Mangkasara’, ) is the capital of the Indonesian province of South Sulawesi. It is the largest city in the region of Eastern Indonesia and the country's fifth-largest urban center after Jakarta, Surabaya, Med ...
had theirs by 1634. A sea wall was the main defense for Gelgel. For cities that did not have city walls, the least it would have had was a stockaded
citadel A citadel is the core fortified area of a town or city. It may be a castle, fortress, or fortified center. The term is a diminutive of "city", meaning "little city", because it is a smaller part of the city of which it is the defensive core. In ...
. This wooden walled area housed the royal citadel or aristocratic compounds such as in Surakarta and
Aceh Aceh ( ), officially the Aceh Province ( ace, Nanggroë Acèh; id, Provinsi Aceh) is the westernmost province of Indonesia. It is located on the northernmost of Sumatra island, with Banda Aceh being its capital and largest city. Granted a s ...
.


China

Large
rammed earth Rammed earth is a technique for constructing foundations, floors, and walls using compacted natural raw materials such as earth, chalk, lime, or gravel. It is an ancient method that has been revived recently as a sustainable building method. ...
walls were built in
ancient China The earliest known written records of the history of China date from as early as 1250 BC, from the Shang dynasty (c. 1600–1046 BC), during the reign of king Wu Ding. Ancient historical texts such as the '' Book of Documents'' (early chapte ...
since the
Shang Dynasty The Shang dynasty (), also known as the Yin dynasty (), was a Chinese royal dynasty founded by Tang of Shang (Cheng Tang) that ruled in the Yellow River valley in the second millennium BC, traditionally succeeding the Xia dynasty and ...
(c. 1600–1050BC), as the capital at ancient Ao had enormous walls built in this fashion (see
siege A siege is a military blockade of a city, or fortress, with the intent of conquering by attrition warfare, attrition, or a well-prepared assault. This derives from la, sedere, lit=to sit. Siege warfare is a form of constant, low-intensity con ...
for more info). Although stone walls were built in China during the
Warring States The Warring States period () was an era in ancient Chinese history characterized by warfare, as well as bureaucratic and military reforms and consolidation. It followed the Spring and Autumn period and concluded with the Qin wars of conquest ...
(481–221BC), mass conversion to stone architecture did not begin in earnest until the
Tang Dynasty The Tang dynasty (, ; zh, t= ), or Tang Empire, was an Dynasties in Chinese history, imperial dynasty of China that ruled from 618 to 907 AD, with an Zhou dynasty (690–705), interregnum between 690 and 705. It was preceded by the Sui dyn ...
(618–907 AD). Sections of the
Great Wall The Great Wall of China (, literally "ten thousand Li (unit), ''li'' wall") is a series of fortifications that were built across the historical northern borders of ancient Chinese states and Imperial China as protection against Eurasian noma ...
had been built prior to the
Qin Dynasty The Qin dynasty ( ; zh, c=秦朝, p=Qín cháo, w=), or Ch'in dynasty in Wade–Giles romanization ( zh, c=, p=, w=Ch'in ch'ao), was the first Dynasties in Chinese history, dynasty of Imperial China. Named for its heartland in Qin (state), ...
(221–207BC) and subsequently connected and fortified during the Qin dynasty, although its present form was mostly an engineering feat and remodeling of the
Ming Dynasty The Ming dynasty (), officially the Great Ming, was an Dynasties in Chinese history, imperial dynasty of China, ruling from 1368 to 1644 following the collapse of the Mongol Empire, Mongol-led Yuan dynasty. The Ming dynasty was the last ort ...
(1368–1644AD). The large walls of Pingyao serve as one example. Likewise, the walls of the
Forbidden City The Forbidden City () is a Chinese palace, palace complex in Dongcheng District, Beijing, China, at the center of the Imperial City, Beijing, Imperial City of Beijing. It is surrounded by numerous opulent imperial gardens and temples includ ...
in
Beijing } Beijing ( ; ; ), alternatively romanized as Peking ( ), is the capital of the People's Republic of China. It is the center of power and development of the country. Beijing is the world's most populous national capital city, with over 21 ...
were established in the early 15th century by the
Yongle Emperor The Yongle Emperor (; pronounced ; 2 May 1360 – 12 August 1424), personal name Zhu Di (), was the third Emperor of the Ming dynasty, reigning from 1402 to 1424. Zhu Di was the fourth son of the Hongwu Emperor, the founder of the Ming dyn ...
. According to
Tonio Andrade Tonio Adam Andrade (born 1968) is an historian of East Asian history and the history of East Asian trading networks. Bibliography * ''Commerce, Culture, and Conflict: Taiwan Under European Rule, 1624–1662''. Yale University Press, 2000. * ''H ...
, the immense thickness of Chinese city walls prevented larger cannons from being developed, since even industrial era artillery had trouble breaching Chinese walls.


Europe

In
ancient Greece Ancient Greece ( el, Ἑλλάς, Hellás) was a northeastern Mediterranean civilization, existing from the Greek Dark Ages of the 12th–9th centuries BC to the end of classical antiquity ( AD 600), that comprised a loose collection of cult ...
, large
stone wall Stone walls are a kind of masonry construction that has been used for thousands of years. The first stone walls were constructed by farmers and primitive people by piling loose field stones into a dry stone wall. Later, mortar and plaster ...
s had been built in
Mycenaean Greece Mycenaean Greece (or the Mycenaean civilization) was the last phase of the Bronze Age The Bronze Age is a historic period, lasting approximately from 3300 BC to 1200 BC, characterized by the use of bronze, the presence of writing in ...
, such as the ancient site of
Mycenae Mycenae ( ; grc, Μυκῆναι or , ''Mykē̂nai'' or ''Mykḗnē'') is an archaeological site near Mykines in Argolis, north-eastern Peloponnese, Greece. It is located about south-west of Athens; north of Argos; and south of Corinth. Th ...
(famous for the huge stone blocks of its '
cyclopean Cyclopean masonry is a type of stonework found in Mycenaean architecture, built with massive limestone boulders, roughly fitted together with minimal clearance between adjacent stones and with clay mortar or no use of mortar. The boulders typic ...
' walls). In classical era Greece, the city of
Athens Athens ( ; el, Αθήνα, Athína ; grc, Ἀθῆναι, Athênai (pl.) ) is both the capital and largest city of Greece. With a population close to four million, it is also the seventh largest city in the European Union. Athens dominates ...
built a long set of parallel stone walls called the
Long Walls Although long walls were built at several locations in ancient Greece, notably Corinth and Megara, the term Long Walls ( grc, Μακρὰ Τείχη ) generally refers to the walls that connected Athens main city to its ports at Piraeus and Phal ...
that reached their guarded seaport at
Piraeus Piraeus ( ; el, Πειραιάς ; grc, Πειραιεύς ) is a port city within the Athens urban area ("Greater Athens"), in the Attica region of Greece. It is located southwest of Athens' city centre, along the east coast of the Saronic ...
. Exceptions were few, but neither ancient
Sparta Sparta ( Doric Greek: Σπάρτα, ''Spártā''; Attic Greek: Σπάρτη, ''Spártē'') was a prominent city-state in Laconia, in ancient Greece. In antiquity, the city-state was known as Lacedaemon (, ), while the name Sparta referre ...
nor ancient
Rome , established_title = Founded , established_date = 753 BC , founder = King Romulus (legendary) , image_map = Map of comune of Rome (metropolitan city of Capital Rome, region Lazio, Italy).svg , map_caption ...
had walls for a long time, choosing to rely on their militaries for defense instead. Initially, these fortifications were simple constructions of wood and earth, which were later replaced by mixed constructions of stones piled on top of each other without mortar. The
Romans Roman or Romans most often refers to: *Rome, the capital city of Italy * Ancient Rome, Roman civilization from 8th century BC to 5th century AD *Roman people, the people of ancient Rome *''Epistle to the Romans'', shortened to ''Romans'', a lette ...
fortified their cities with massive, mortar-bound stone walls. Among these are the largely extant Aurelian Walls of
Rome , established_title = Founded , established_date = 753 BC , founder = King Romulus (legendary) , image_map = Map of comune of Rome (metropolitan city of Capital Rome, region Lazio, Italy).svg , map_caption ...
and the
Theodosian Walls The Walls of Constantinople ( el, Τείχη της Κωνσταντινουπόλεως) are a series of defensive stone walls that have surrounded and protected the city of Constantinople (today Istanbul in Turkey) since its founding as the ...
of
Constantinople la, Constantinopolis ota, قسطنطينيه , alternate_name = Byzantion (earlier Greek name), Nova Roma ("New Rome"), Miklagard/Miklagarth (Old Norse), Tsargrad ( Slavic), Qustantiniya (Arabic), Basileuousa ("Queen of Cities"), Megalopolis (" ...
, together with partial remains elsewhere. These are mostly city gates, like the
Porta Nigra The Porta Nigra (Latin for ''black gate'') is a large Roman city gate in Trier, Germany. It is today the largest Roman city gate north of the Alps. It was designated as part of the Roman Monuments, Cathedral of St Peter and Church of Our Lady in ...
in
Trier Trier ( , ; lb, Tréier ), formerly known in English as Trèves ( ;) and Triers (see also names in other languages), is a city on the banks of the Moselle in Germany. It lies in a valley between low vine-covered hills of red sandstone in the ...
or
Newport Arch Newport Arch is a 3rd-century Roman gate in the city of Lincoln, Lincolnshire. It is a Scheduled monument and Grade I listed building and is reputedly the oldest arch in the United Kingdom still used by traffic. History The arch was remodelled ...
in
Lincoln Lincoln most commonly refers to: * Abraham Lincoln (1809–1865), the sixteenth president of the United States * Lincoln, England, cathedral city and county town of Lincolnshire, England * Lincoln, Nebraska, the capital of Nebraska, U.S. * Lincol ...
. In Central Europe, the
Celts The Celts (, see pronunciation for different usages) or Celtic peoples () are. "CELTS location: Greater Europe time period: Second millennium B.C.E. to present ancestry: Celtic a collection of Indo-European peoples. "The Celts, an ancien ...
built large fortified settlements which the Romans called
oppida An ''oppidum'' (plural ''oppida'') is a large fortified Iron Age settlement or town. ''Oppida'' are primarily associated with the Celtic late La Tène culture, emerging during the 2nd and 1st centuries BC, spread across Europe, stretch ...
, whose walls seem partially influenced by those built in the Mediterranean. The
fortifications A fortification is a military construction or building designed for the defense of territories in warfare, and is also used to establish rule in a region during peacetime. The term is derived from Latin ''fortis'' ("strong") and ''facere'' ...
were continuously expanded and improved. Apart from these, the early
Middle Ages In the history of Europe, the Middle Ages or medieval period lasted approximately from the late 5th to the late 15th centuries, similar to the post-classical period of global history. It began with the fall of the Western Roman Empire a ...
also saw the creation of some towns built around castles. These cities were only rarely protected by simple stone walls and more usually by a combination of both walls and
ditches A ditch is a small to moderate divot created to channel water. A ditch can be used for drainage, to drain water from low-lying areas, alongside roadways or fields, or to channel water from a more distant source for plant irrigation. Ditches ar ...
. From the 12th century AD hundreds of settlements of all sizes were founded all across Europe, which very often obtained the right of fortification soon afterwards. Several medieval town walls have survived into the modern age, such as the walled towns of Austria,
walls of Tallinn The Walls of Tallinn are the medieval defensive walls constructed around the city of Tallinn in Estonia. History The first wall around Tallinn was ordered to be constructed by Margaret Sambiria in 1265 resulting in its name, the 'Margaret Wall ...
, or the town walls of
York York is a cathedral city with Roman origins, sited at the confluence of the rivers Ouse and Foss in North Yorkshire, England. It is the historic county town of Yorkshire. The city has many historic buildings and other structures, such as a ...
and
Canterbury Canterbury (, ) is a City status in the United Kingdom, cathedral city and UNESCO World Heritage Site, situated in the heart of the City of Canterbury local government district of Kent, England. It lies on the River Stour, Kent, River Stour. ...
in England, as well as Nordlingen,
Dinkelsbühl Dinkelsbühl () is a historic town in Central Franconia, a region of Germany that is now part of the state of Bavaria, in southern Germany. Dinkelsbühl is a former free imperial city of the Holy Roman Empire. In local government terms, Dinkelsb ...
and
Rothenburg ob der Tauber Rothenburg ob der Tauber () is a town in the district of Ansbach of Mittelfranken (Middle Franconia), the Franconia region of Bavaria, Germany. It is well known for its well-preserved medieval old town, a destination for tourists from around the ...
in Germany. In Spain, Avila and Tossa del Mar hosts surviving medieval walls while
Lugo Lugo (, ; la, Lucus Augusti) is a city in northwestern Spain in the autonomous communities of Spain, autonomous community of Galicia (Spain), Galicia. It is the capital of the Lugo (province), province of Lugo. The municipality had a population ...
has an intact Roman wall. The founding of urban centers was an important means of territorial expansion and many cities, especially in central and eastern Europe, were founded for this purpose during the period of
Eastern settlement The Eastern Settlement ( non, Eystribygð ) was the first and by far the larger of the two main areas of Norse Greenland, settled by Norsemen from Iceland. At its peak, it contained approximately 4,000 inhabitants. The last written record from t ...
. These cities are easy to recognise due to their regular layout and large market spaces. The fortifications of these settlements were continuously improved to reflect the current level of military development.


Gunpowder era


Chinese city walls

While gunpowder and cannons were invented in China, China never developed wall breaking artillery to the same extent as other parts of the world. Part of the reason is probably because Chinese walls were already highly resistant to artillery and discouraged increasing the size of cannons. In the mid-twentieth century a European expert in fortification commented on their immensity: "in China … the principal towns are surrounded to the present day by walls so substantial, lofty, and formidable that the medieval fortifications of Europe are puny in comparison." Chinese walls were thick. The eastern wall of Ancient Linzi, established in 859 BC, had a maximum thickness of 43 metres and an average thickness of 20-30 metres. Ming prefectural and provincial capital walls were thick at the base and at the top. In Europe the height of wall construction was reached under the
Roman Empire The Roman Empire ( la, Imperium Romanum ; grc-gre, Βασιλεία τῶν Ῥωμαίων, Basileía tôn Rhōmaíōn) was the post-Republican period of ancient Rome. As a polity, it included large territorial holdings around the Mediterr ...
, whose walls often reached in height, the same as many Chinese city walls, but were only thick. Rome's Servian Walls reached in thickness and in height. Other fortifications also reached these specifications across the empire, but all these paled in comparison to contemporary Chinese walls, which could reach a thickness of at the base in extreme cases. Even the walls of Constantinople which have been described as "the most famous and complicated system of defence in the civilized world," could not match up to a major Chinese city wall. Had both the outer and inner walls of Constantinople been combined they would have only reached roughly a bit more than a third the width of a major wall in China. According to
Philo Philo of Alexandria (; grc, Φίλων, Phílōn; he, יְדִידְיָה, Yəḏīḏyāh (Jedediah); ), also called Philo Judaeus, was a Hellenistic Jewish philosopher who lived in Alexandria, in the Roman province of Egypt. Philo's de ...
the width of a wall had to be thick to be able to withstand ancient (non-gunpowder) siege engines. European walls of the 1200s and 1300s could reach the Roman equivalents but rarely exceeded them in length, width, and height, remaining around thick. It is apt to note that when referring to a very thick wall in medieval Europe, what is usually meant is a wall of in width, which would have been considered thin in a Chinese context. There are some exceptions such as the
Hillfort of Otzenhausen The Celtic hill fort of Otzenhausen is one of the biggest fortifications the Celts ever constructed. It was built by Gauls of the Treveri tribe, who lived in the region north of the fort. The fort is located on top of the ''Dollberg'', a hill near ...
, a Celtic ringfort with a thickness of in some parts, but Celtic fort-building practices died out in the early medieval period. Andrade goes on to note that the walls of the ''marketplace'' of Chang'an were thicker than the walls of major European capitals. Aside from their immense size, Chinese walls were also structurally different from the ones built in medieval Europe. Whereas European walls were mostly constructed of stone interspersed with gravel or rubble filling and bonded by limestone mortar, Chinese walls had tamped earthen cores which absorbed the energy of artillery shots. Walls were constructed using wooden frameworks which were filled with layers of earth tamped down to a highly compact state, and once that was completed the frameworks were removed for use in the next wall section. Starting from the Song dynasty these walls were improved with an outer layer of bricks or stone to prevent corrosion, and during the Ming, earthworks were interspersed with stone and rubble. Most Chinese walls were also sloped rather than vertical to better deflect projectile energy. The Chinese Wall Theory essentially rests on a cost benefit hypothesis, where the Ming recognized the highly resistant nature of their walls to structural damage, and could not imagine any affordable development of the guns available to them at the time to be capable of breaching said walls. Even as late as the 1490s a Florentine diplomat considered the French claim that "their artillery is capable of creating a breach in a wall of eight feet in thickness" to be ridiculous and the French "braggarts by nature". In fact ''twentieth'' century explosive shells had some difficulty creating a breach in tamped earthen walls.


Bastions and star forts

As a response to gunpowder artillery, European fortifications began displaying architectural principles such as lower and thicker walls in the mid-1400s. Cannon towers were built with artillery rooms where cannons could discharge fire from slits in the walls. However this proved problematic as the slow rate of fire, reverberating concussions, and noxious fumes produced greatly hindered defenders. Gun towers also limited the size and number of cannon placements because the rooms could only be built so big. Notable surviving artillery towers include a seven layer defensive structure built in 1480 at
Fougères Fougères (; br, Felger; Gallo: ''Foujerr'') is a commune and a sub-prefecture of the Ille-et-Vilaine department in the region of Brittany in northwestern France. As of 2017, Fougères had 20,418 inhabitants. The Fougères area comprises appr ...
in
Brittany Brittany (; french: link=no, Bretagne ; br, Breizh, or ; Gallo language, Gallo: ''Bertaèyn'' ) is a peninsula, Historical region, historical country and cultural area in the west of modern France, covering the western part of what was known ...
, and a four layer tower built in 1479 at Querfurth in Saxony. The star fort, also known as the bastion fort, ''trace italienne'', or renaissance fortress, was a style of fortification that became popular in Europe during the 16th century. The bastion and star fort was developed in Italy, where the Florentine engineer
Giuliano da Sangallo Giuliano da Sangallo (c. 1445 – 1516) was an Italian sculptor, architect and military engineer active during the Italian Renaissance. He is known primarily for being the favored architect of Lorenzo de' Medici, his patron. In this role, Giulia ...
(1445–1516) compiled a comprehensive defensive plan using the geometric bastion and full ''trace italienne'' that became widespread in Europe. The main distinguishing features of the star fort were its angle bastions, each placed to support their neighbor with lethal crossfire, covering all angles, making them extremely difficult to engage with and attack. Angle bastions consisted of two faces and two flanks. Artillery positions positioned at the flanks could fire parallel into the opposite bastion's line of fire, thus providing two lines of cover fire against an armed assault on the wall, and preventing mining parties from finding refuge. Meanwhile, artillery positioned on the bastion platform could fire frontally from the two faces, also providing overlapping fire with the opposite bastion. Overlapping mutually supporting defensive fire was the greatest advantage enjoyed by the star fort. As a result, sieges lasted longer and became more difficult affairs. By the 1530s the bastion fort had become the dominant defensive structure in Italy. Outside Europe, the star fort became an "engine of European expansion," and acted as a force multiplier so that small European garrisons could hold out against numerically superior forces. Wherever star forts were erected the natives experienced great difficulty in uprooting European invaders. In China, Sun Yuanhua advocated for the construction of angled bastion forts in his ''Xifashenji'' so that their cannons could better support each other. The officials Han Yun and Han Lin noted that cannons on square forts could not support each side as well as bastion forts. Their efforts to construct bastion forts, and their results, were limited. Ma Weicheng built two bastion forts in his home county, which helped fend off a Qing incursion in 1638. By 1641, there were ten bastion forts in the county. Before bastion forts could spread any further, the Ming dynasty fell in 1644, and they were largely forgotten as the Qing dynasty was on the offensive most of the time and had no use for them.


Decline

In the wake of city growth and the ensuing change of defensive strategy, focusing more on the defense of
fort A fortification is a military construction or building designed for the defense of territories in warfare, and is also used to establish rule in a region during peacetime. The term is derived from Latin ''fortis'' ("strong") and ''facere'' ...
s around cities, many city walls were demolished. Also, the invention of gunpowder rendered walls less effective, as siege cannons could then be used to blast through walls, allowing armies to simply march through. Today, the presence of former city fortifications can often only be deduced from the presence of ditches,
ring road A ring road (also known as circular road, beltline, beltway, circumferential (high)way, loop, bypass or orbital) is a road or a series of connected roads encircling a town, city, or country. The most common purpose of a ring road is to assist i ...
s or parks. Furthermore, some street names hint at the presence of fortifications in times past, for example when words such as "wall" or "glacis" occur. In the 19th century, less emphasis was placed on preserving the fortifications for the sake of their architectural or historical value on the one hand, complete fortifications were restored (
Carcassonne Carcassonne (, also , , ; ; la, Carcaso) is a French fortified city in the department of Aude, in the region of Occitanie. It is the prefecture of the department. Inhabited since the Neolithic, Carcassonne is located in the plain of the Au ...
), on the other hand many structures were demolished in an effort to modernize the cities. One exception to this is the "monument preservation" law by the Bavarian King
Ludwig I of Bavaria en, Louis Charles Augustus , image = Joseph Karl Stieler - King Ludwig I in his Coronation Robes - WGA21796.jpg , caption = Portrait by Joseph Stieler, 1825 , succession=King of Bavaria , reign = , coronation ...
, which led to the nearly complete preservation of many monuments such as the
Rothenburg ob der Tauber Rothenburg ob der Tauber () is a town in the district of Ansbach of Mittelfranken (Middle Franconia), the Franconia region of Bavaria, Germany. It is well known for its well-preserved medieval old town, a destination for tourists from around the ...
,
Nördlingen Nördlingen (; Swabian: ''Nearle'' or ''Nearleng'') is a town in the Donau-Ries district, in Swabia, Bavaria, Germany, with a population of approximately 20,674. It is located approximately east of Stuttgart, and northwest of Munich. It was b ...
and
Dinkelsbühl Dinkelsbühl () is a historic town in Central Franconia, a region of Germany that is now part of the state of Bavaria, in southern Germany. Dinkelsbühl is a former free imperial city of the Holy Roman Empire. In local government terms, Dinkelsb ...
. The countless small fortified towns in the
Franconia Franconia (german: Franken, ; Franconian dialect: ''Franggn'' ; bar, Frankn) is a region of Germany, characterised by its culture and Franconian dialect (German: ''Fränkisch''). The three administrative regions of Lower, Middle and Upper Fr ...
region were also preserved as a consequence of this edict.


Modern era

Walls and fortified wall structures were still built in the modern era. They did not, however, have the original purpose of being a structure able to resist a prolonged siege or bombardment. Modern examples of defensive walls include: * Berlin's city wall from the 1730s to the 1860s was partially made of wood. Its primary purpose was to enable the city to impose tolls on goods and, secondarily, also served to prevent the desertion of soldiers from the garrison in Berlin. * The
Berlin Wall The Berlin Wall (german: Berliner Mauer, ) was a guarded concrete barrier that encircled West Berlin from 1961 to 1989, separating it from East Berlin and East Germany (GDR). Construction of the Berlin Wall was commenced by the government ...
(1961 to 1989) did not exclusively serve the purpose of protection of an enclosed settlement. One of its purposes was to prevent the crossing of the Berlin border between the
German Democratic Republic German(s) may refer to: * Germany (of or related to) **Germania (historical use) * Germans, citizens of Germany, people of German ancestry, or native speakers of the German language ** For citizens of Germany, see also German nationality law **Ger ...
and the
West German West Germany is the colloquial term used to indicate the Federal Republic of Germany (FRG; german: Bundesrepublik Deutschland , BRD) between its formation on 23 May 1949 and the German reunification through the accession of East Germany on 3 O ...
exclave An enclave is a territory (or a small territory apart of a larger one) that is entirely surrounded by the territory of one other state or entity. Enclaves may also exist within territorial waters. ''Enclave'' is sometimes used improperly to deno ...
of
west-Berlin West Berlin (german: Berlin (West) or , ) was a political enclave which comprised the western part of Berlin during the years of the Cold War. Although West Berlin was de jure not part of West Germany, lacked any sovereignty, and was under mi ...
. * The Nicosia Wall along the Green Line divides North and South Cyprus. * In the 20th century and after, many enclaved Jewish settlements in Israeli occupied territory in the West Bank were and are surrounded by fortified walls *
Mexico–United States barrier The Mexico–United States barrier ( es, barrera Estados Unidos–México), also known as the border wall, is a series of vertical barriers along the Mexico–United States border intended to reduce illegal immigration to the United States ...
, a wall advocated by U.S. President
Donald Trump Donald John Trump (born June 14, 1946) is an American politician, media personality, and businessman who served as the 45th president of the United States from 2017 to 2021. Trump graduated from the Wharton School of the University of Pe ...
for the
Mexico–United States border The Mexico–United States border ( es, frontera Estados Unidos–México) is an international border separating Mexico and the United States, extending from the Pacific Ocean in the west to the Gulf of Mexico in the east. The border traver ...
to prevent illegal immigration, drug smuggling, human trafficking, and entry of potential terrorists *
Belfast Belfast ( , ; from ga, Béal Feirste , meaning 'mouth of the sand-bank ford') is the capital and largest city of Northern Ireland, standing on the banks of the River Lagan on the east coast. It is the 12th-largest city in the United Kingdo ...
,
Northern Ireland Northern Ireland ( ga, Tuaisceart Éireann ; sco, label= Ulster-Scots, Norlin Airlann) is a part of the United Kingdom, situated in the north-east of the island of Ireland, that is variously described as a country, province or region. Nort ...
by the "
peace lines The peace lines or peace walls are a series of separation barriers in Northern Ireland that separate predominantly republican and nationalist Catholic neighbourhoods from predominantly loyalist and unionist Protestant neighbourhoods. T ...
". *
Gated communities A gated community (or walled community) is a form of residential community or housing estate containing strictly controlled entrances for pedestrians, bicycles, and automobiles, and often characterized by a closed perimeter of walls and fences. ...
are modern residential neighborhoods where access is controlled, often prohibiting through-travelers or non-residents via a wall and guards Additionally, in some countries, different embassies may be grouped together in a single "embassy district", enclosed by a fortified complex with walls and towersthis usually occurs in regions where the embassies run a high risk of being target of attacks. An early example of such a compound was the
Legation Quarter The Peking Legation Quarter was the area in Peking (Beijing), China where a number of foreign legations were located between 1861 and 1959. In the Chinese language, the area is known as ''Dong Jiaomin Xiang'' (), which is the name of the ''hutong ...
in
Beijing } Beijing ( ; ; ), alternatively romanized as Peking ( ), is the capital of the People's Republic of China. It is the center of power and development of the country. Beijing is the world's most populous national capital city, with over 21 ...
in the late 19th and early 20th centuries. Most of these modern city walls are made of steel and concrete. Vertical concrete plates are put together so as to allow the least space in between them, and are rooted firmly in the ground. The top of the wall is often protruding and beset with
barbed wire A close-up view of a barbed wire Roll of modern agricultural barbed wire Barbed wire, also known as barb wire, is a type of steel fencing wire constructed with sharp edges or points arranged at intervals along the strands. Its primary use is t ...
in order to make climbing them more difficult. These walls are usually built in straight lines and covered by watchtowers at the corners. Double walls with an interstitial "zone of fire", as the former Berlin Wall had, are now rare. In September 2014, Ukraine announced the construction of the "European Rampart" alongside its border with Russia to be able to successfully apply for a visa-free movement with the European Union.


Composition

At its simplest, a defensive wall consists of a wall enclosure and its gates. For the most part, the top of the walls were accessible, with the outside of the walls having tall
parapet A parapet is a barrier that is an extension of the wall at the edge of a roof, terrace, balcony, walkway or other structure. The word comes ultimately from the Italian ''parapetto'' (''parare'' 'to cover/defend' and ''petto'' 'chest/breast'). Whe ...
s with
embrasure An embrasure (or crenel or crenelle; sometimes called gunhole in the domain of gunpowder-era architecture) is the opening in a battlement between two raised solid portions (merlons). Alternatively, an embrasure can be a space hollowed out ...
s or
merlon A merlon is the solid upright section of a battlement (a crenellated parapet) in medieval architecture or fortifications.Friar, Stephen (2003). ''The Sutton Companion to Castles'', Sutton Publishing, Stroud, 2003, p. 202. Merlons are sometimes ...
s. North of the Alps, this passageway at the top of the walls occasionally had a roof. In addition to this, many different enhancements were made over the course of the centuries: * City ditch: a ditch dug in front of the walls, occasionally filled with water to form a
moat A moat is a deep, broad ditch, either dry or filled with water, that is dug and surrounds a castle, fortification, building or town, historically to provide it with a preliminary line of defence. In some places moats evolved into more extensive ...
. *
Gate tower A gate tower (german: Torturm) is a tower built over or next to a major gateway. Usually it is part of a medieval fortification. This may be a town or city wall, fortress, castle or castle chapel. The gate tower may be built as a twin tower on ...
: a tower built next to, or on top of the city gates to better defend the city gates. *
Wall tower A fortified tower (also defensive tower or castle tower or, in context, just tower) is one of the defensive structures used in fortifications, such as castles, along with curtain walls. Castle towers can have a variety of different shapes and ful ...
: a tower built on top of a segment of the wall, which usually extended outwards slightly, so as to be able to observe the exterior of the walls on either side. In addition to arrow slits, ballistae, catapults and cannons could be mounted on top for extra defence. * Pre-wall: wall built outside the wall proper, usually of lesser height the space in between was usually further subdivided by additional walls. * Additional obstacles in front of the walls. The defensive towers of west and south European fortifications in the Middle Ages were often very regularly and uniformly constructed (cf.
Ávila Ávila (, , ) is a city of Spain located in the autonomous community of Castile and León. It is the capital and most populated municipality of the Province of Ávila. It lies on the right bank of the Adaja river. Located more than 1,130 m abov ...
,
Provins Provins () is a commune in the Seine-et-Marne department in the Île-de-France region in north-central France. Known for its well-preserved medieval architecture and importance throughout the Middle Ages as an economic center and a host of annu ...
), whereas Central European city walls tend to show a variety of different styles. In these cases the gate and wall towers often reach up to considerable heights, and gates equipped with two towers on either side are much rarer. Apart from having a purely military and defensive purpose, towers also played a representative and artistic role in the conception of a fortified complex. The architecture of the city thus competed with that of the castle of the noblemen and city walls were often a manifestation of the pride of a particular city. Urban areas outside the city walls, so-called
Vorstädte In German language, German, a Vorstadt is an area of a city that is outside the Altstadt (city center) but tightly connected to it and densely populated, thus distinguishing itself from a ''Vorort'' (suburb). Historically, a ''Vorstadt'' ("suburb" ...
, were often enclosed by their own set of walls and integrated into the defense of the city. These areas were often inhabited by the poorer population and held the "noxious trades". In many cities, a new wall was built once the city had grown outside of the old wall. This can often still be seen in the layout of the city, for example in
Nördlingen Nördlingen (; Swabian: ''Nearle'' or ''Nearleng'') is a town in the Donau-Ries district, in Swabia, Bavaria, Germany, with a population of approximately 20,674. It is located approximately east of Stuttgart, and northwest of Munich. It was b ...
, and sometimes even a few of the old gate towers are preserved, such as the ''white tower'' in
Nuremberg Nuremberg ( ; german: link=no, Nürnberg ; in the local East Franconian dialect: ''Nämberch'' ) is the second-largest city of the German state of Bavaria after its capital Munich, and its 518,370 (2019) inhabitants make it the 14th-largest ...
. Additional constructions prevented the circumvention of the city, through which many important trade routes passed, thus ensuring that tolls were paid when the caravans passed through the city gates, and that the local market was visited by the trade caravans. Furthermore, additional signaling and observation towers were frequently built outside the city, and were sometimes fortified in a castle-like fashion. The border of the area of influence of the city was often partially or fully defended by elaborate ditches, walls and hedges. The crossing points were usually guarded by gates or gate houses. These defenses were regularly checked by riders, who often also served as the gate keepers. Long stretches of these defenses can still be seen to this day, and even some gates are still intact. To further protect their territory, rich cities also established castles in their area of influence. An example of this practice is the Romanian
Bran Castle Bran Castle ( ro, Castelul Bran; german: Schloss Bran; hu, Törcsvári kastély) is a castle in Bran, southwest of Brașov. It is a national monument and landmark in Transylvania. The fortress is on the Transylvanian side of the historical bo ...
, which was intended to protect nearby Kronstadt (today's Braşov). The city walls were often connected to the fortifications of hill castles via additional walls. Thus the defenses were made up of city and castle fortifications taken together. Several examples of this are preserved, for example in Germany
Hirschhorn Hirschhorn is derived from German composite word "Hirsch" (deer) and "Horn" (horn), part of a deer's antlers. A variation is Hirshhorn. It may refer to: * Hirschhorn (Neckar), a town in Hesse, Germany * Hirschhorn, Rhineland-Palatinate, a municipal ...
on the Neckar,
Königsberg Königsberg (, ) was the historic Prussian city that is now Kaliningrad, Russia. Königsberg was founded in 1255 on the site of the ancient Old Prussian settlement ''Twangste'' by the Teutonic Knights during the Northern Crusades, and was named ...
and
Pappenheim Pappenheim is a town in the Weißenburg-Gunzenhausen district, in Bavaria, Germany. It is situated on the river Altmühl, 11 km south of Weißenburg in Bayern. History Historically, Pappenheim was a statelet within Holy Roman Empire. It ...
, Franken, Burghausen in
Oberbayern Upper Bavaria (german: Oberbayern, ; ) is one of the seven administrative districts of Bavaria, Germany. Geography Upper Bavaria is located in the southern portion of Bavaria, and is centered on the city of Munich, both state capital and seat o ...
and many more. A few castles were more directly incorporated into the defensive strategy of the city (e.g.
Nuremberg Nuremberg ( ; german: link=no, Nürnberg ; in the local East Franconian dialect: ''Nämberch'' ) is the second-largest city of the German state of Bavaria after its capital Munich, and its 518,370 (2019) inhabitants make it the 14th-largest ...
,
Zons Zons (), formerly known as Feste Zons ''( Fortress Zons''), today officially called ''Stadt Zons'' (''Zons Town'') is an old town in Germany on the west bank of the Lower Rhine between Cologne and Düsseldorf. It has been a part (Stadtteil) of th ...
,
Carcassonne Carcassonne (, also , , ; ; la, Carcaso) is a French fortified city in the department of Aude, in the region of Occitanie. It is the prefecture of the department. Inhabited since the Neolithic, Carcassonne is located in the plain of the Au ...
), or the cities were directly outside the castle as a sort of "pre-castle" (Coucy-le-Chateau,
Conwy Conwy (, ), previously known in English as Conway, is a walled market town, community and the administrative centre of Conwy County Borough in North Wales. The walled town and castle stand on the west bank of the River Conwy, facing Deganwy on ...
and others). Larger cities often had multiple stewards for example
Augsburg Augsburg (; bar , Augschburg , links=https://en.wikipedia.org/wiki/Swabian_German , label=Swabian German, , ) is a city in Swabia, Bavaria, Germany, around west of Bavarian capital Munich. It is a university town and regional seat of the ' ...
was divided into a Reichstadt and a clerical city. These different parts were often separated by their own fortifications.


Dimensions of famous city walls


Gallery


Africa


Americas


Asia


China


Europe


Roman


See also

*
List of cities with defensive walls The following cities have, or historically had, defensive walls. Africa Algeria * Algiers * Ghardaïa * Timimoun Egypt * Al-Fustat * Cairo * Damietta See List of Egypt castles, forts, fortifications and city walls. Ethiopia * Harar Libya * ...
*
List of town walls in England and Wales This list of town walls in England and Wales describes the fortified walls built and maintained around these towns and cities from the 1st century AD onwards. The first town walls were built by the Romans, following their conquest of Britain ...
*
List of walls See List of fortifications for a list of notable fortified structures. For city walls in particular, see List of cities with defensive walls. Pre-modern fortifications * The Great Wall of China, China - part of UNESCO site 438,. This is ...
*
Ancient Roman defensive walls Defensive walls are a feature of ancient Roman architecture. The Romans generally fortified cities, rather than building stand-alone fortresses, but there are some fortified camps, such as the Saxon Shore forts like Porchester Castle in England ...
* Barricade *
Border barrier A border barrier is a separation barrier that runs along or near an international border. Such barriers are typically constructed for border control purposes such as curbing illegal immigration, human trafficking, and smuggling. Some such barr ...
*
Chinese city wall Chinese city walls () refer to defensive systems used to protect towns and cities in China in pre-modern times. In addition to walls, city defenses often included towers and gates. Meaning of the word ''Chengqiang'' The most specific Chines ...
*
Citadel A citadel is the core fortified area of a town or city. It may be a castle, fortress, or fortified center. The term is a diminutive of "city", meaning "little city", because it is a smaller part of the city of which it is the defensive core. In ...
* Glacis *
Medieval fortification Medieval fortification refers to medieval military methods that cover the development of fortification construction and use in Europe, roughly from the fall of the Western Roman Empire to the Renaissance. During this millennium, fortifications ...
*
Mural crown A mural crown ( la, corona muralis) is a crown or headpiece representing city walls, towers, or fortresses. In classical antiquity, it was an emblem of tutelary deities who watched over a city, and among the Romans a military decoration. Later ...
* Murus Dacicus *
Murus Gallicus ''Murus gallicus'' or Gallic wall is a method of construction of defensive walls used to protect Iron Age hillforts and ''oppida'' of the La Tene period in Western Europe. Basic features The distinctive features are: * earth or rubble f ...
*
Talus (fortification) In architecture, the talus is a feature of some late medieval castles, especially prevalent in crusader constructions. It consists of a battered (sloping) face at the base of a fortified wall. Feature The slope acts as an effective defensive m ...


Notes


References

* . * * * * Monika Porsche: ''Stadtmauer und Stadtentstehung'' Untersuchungen zur frühen Stadtbefestigung im mittelalterlichen Deutschen Reich. - Hertingen, 2000. . * * * {{Authority control Castle architecture Fortification (architectural elements)


External links


San Juan City Walls