A moat is a deep, broad ditch dug around a
castle
A castle is a type of fortification, fortified structure built during the Middle Ages predominantly by the nobility or royalty and by Military order (monastic society), military orders. Scholars usually consider a ''castle'' to be the private ...
,
fortification
A fortification (also called a fort, fortress, fastness, or stronghold) is a military construction designed for the defense of territories in warfare, and is used to establish rule in a region during peacetime. The term is derived from Lati ...
,
building
A building or edifice is an enclosed Structure#Load-bearing, structure with a roof, walls and window, windows, usually standing permanently in one place, such as a house or factory. Buildings come in a variety of sizes, shapes, and functions, a ...
, or town, historically to provide it with a preliminary line of
defence. Moats can be dry or filled with water. In some places, moats evolved into more extensive water defences, including natural or artificial lakes,
dam
A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use, aqua ...
s and
sluices. In older fortifications, such as
hillfort
A hillfort is a type of fortification, fortified refuge or defended settlement located to exploit a rise in elevation for defensive advantage. They are typical of the late Bronze Age Europe, European Bronze Age and Iron Age Europe, Iron Age. So ...
s, they are usually referred to simply as
ditches, although the function is similar. In later periods, moats or water defences may be largely ornamental. They could also act as a sewer.
Historical use
Ancient
Some of the earliest evidence of moats has been uncovered around
ancient Egypt
Ancient Egypt () was a cradle of civilization concentrated along the lower reaches of the Nile River in Northeast Africa. It emerged from prehistoric Egypt around 3150BC (according to conventional Egyptian chronology), when Upper and Lower E ...
ian fortresses. One example is at
Buhen, a settlement excavated in
Nubia
Nubia (, Nobiin language, Nobiin: , ) is a region along the Nile river encompassing the area between the confluence of the Blue Nile, Blue and White Nile, White Niles (in Khartoum in central Sudan), and the Cataracts of the Nile, first cataract ...
. Other evidence of ancient moats is found in the ruins of Babylon, and in reliefs from ancient Egypt,
Assyria
Assyria (Neo-Assyrian cuneiform: , ''māt Aššur'') was a major ancient Mesopotamian civilization that existed as a city-state from the 21st century BC to the 14th century BC and eventually expanded into an empire from the 14th century BC t ...
, and other cultures in the region.
Evidence of early moats around settlements has been discovered in many archaeological sites throughout Southeast Asia, including Noen U-Loke, Ban Non Khrua Chut, Ban Makham Thae and Ban Non Wat. The use of the moats could have been either for defensive or agriculture purposes.
Medieval

Moats were excavated around
castle
A castle is a type of fortification, fortified structure built during the Middle Ages predominantly by the nobility or royalty and by Military order (monastic society), military orders. Scholars usually consider a ''castle'' to be the private ...
s and other fortifications as part of the defensive system as an obstacle immediately outside the
walls. In suitable locations, they might be filled with water. A moat made access to the walls difficult for siege weapons such as
siege tower
A Roman siege tower or breaching tower (or in the Middle Ages, a belfry''Castle: Stephen Biesty's Cross-Sections''. Dorling Kindersley Pub (T); 1st American edition (September 1994). Siege towers were invented in 300 BC. ) is a specialized siege ...
s and
battering ram
A battering ram is a siege engine that originated in ancient times and was designed to break open the masonry walls of fortifications or splinter their wooden gates. In its simplest form, a battering ram is just a large, heavy log carried ...
s, which needed to be brought up against a wall to be effective. A water-filled moat made the practice of
mining
Mining is the Resource extraction, extraction of valuable geological materials and minerals from the surface of the Earth. Mining is required to obtain most materials that cannot be grown through agriculture, agricultural processes, or feasib ...
– digging tunnels under the castles in order to effect a collapse of the defences – very difficult as well. ''Segmented moats'' have one dry section and one section filled with water. Dry moats that cut across the narrow part of a spur or peninsula are called ''
neck ditches''. Moats separating different elements of a castle, such as the inner and outer wards, are ''cross ditches''.
The word was adapted in
Middle English
Middle English (abbreviated to ME) is a form of the English language that was spoken after the Norman Conquest of 1066, until the late 15th century. The English language underwent distinct variations and developments following the Old English pe ...
from the
Old French
Old French (, , ; ) was the language spoken in most of the northern half of France approximately between the late 8th [2-4; we might wonder whether there's a point at which it's appropriate to talk of the beginnings of French, that is, when it wa ...
() and was first applied to the central mound on which a castle was erected (see Motte and bailey) and then came to be applied to the excavated ring, a 'dry moat'. The shared derivation implies that the two features were closely related and possibly constructed at the same time. The term ''moat'' is also applied to natural formations reminiscent of the artificial structure and to similar modern architectural features.
Later western fortification
With the introduction of siege
artillery
Artillery consists of ranged weapons that launch Ammunition, munitions far beyond the range and power of infantry firearms. Early artillery development focused on the ability to breach defensive walls and fortifications during sieges, and l ...
, a new style of fortification emerged in the 16th century using low walls and projecting strong points called
bastion
A bastion is a structure projecting outward from the curtain wall of a fortification, most commonly angular in shape and positioned at the corners of the fort. The fully developed bastion consists of two faces and two flanks, with fire from the ...
s, which was known as the ''
trace italienne
A bastion fort or ''trace italienne'' (a phrase derived from non-standard French, meaning 'Italian outline') is a fortification in a style developed during the early modern period in response to the ascendancy of gunpowder weapons such as c ...
''. The walls were further protected from infantry attack by wet or dry moats, sometimes in elaborate systems. When this style of fortification was superseded by lines of
polygonal forts in the mid-19th century, moats continued to be used for close protection.
Africa
The
Walls of Benin
The Benin Moat (), also known as the Benin Iya, or Walls of Benin, are a series of massive earthworks encircling Benin City in Nigeria's Edo State. These moats have deep historical roots, with evidence suggesting their existence before the est ...
were a combination of ramparts and moats, called Iya, used as a defence of the capital
Benin City
Benin City serves as the Capital city, capital and largest
Metropolitan area, metropolitan centre of Edo State, situated in Nigeria, southern Nigeria. It ranks as the List of Nigerian cities by population, fourth-most populous city in Niger ...
in present-day Edo State of Nigeria. It was considered the largest man-made structure lengthwise, second only to the
Great Wall of China
The Great Wall of China (, literally "ten thousand ''li'' long wall") is a series of fortifications in China. They were built across the historical northern borders of ancient Chinese states and Imperial China as protection against vario ...
and the largest earthwork in the world. Recent work by Patrick Darling has established it as the largest man-made structure in the world, larger than
Sungbo's Eredo, also in Nigeria. It enclosed of community lands. Its length was over of earth boundaries. It was estimated that earliest construction began in 800 and continued into the mid-15th century.
The walls are built of a ditch and dike structure, the ditch dug to form an inner moat with the excavated earth used to form the exterior rampart.
The Benin Walls were ravaged by the British in 1897. Scattered pieces of the walls remain in Edo, with material being used by the locals for building purposes. The walls continue to be torn down for real-estate developments.
The Walls of Benin City were the world's largest man-made structure.
Fred Pearce wrote in ''
New Scientist
''New Scientist'' is a popular science magazine covering all aspects of science and technology. Based in London, it publishes weekly English-language editions in the United Kingdom, the United States and Australia. An editorially separate organ ...
'':
They extend for some 16,000 kilometres in all, in a mosaic of more than 500 interconnected settlement boundaries. They cover 6,500 square kilometres and were all dug by the Edo people. In all, they are four times longer than the Great Wall of China, and consumed a hundred times more material than the Great Pyramid of Cheops. They took an estimated 150 million hours of digging to construct, and are perhaps the largest single archaeological phenomenon on the planet.
Asia
Japanese castle
are fortresses constructed primarily of wood and stone. They evolved from the wooden stockades of earlier centuries and came into their best-known form in the 16th century. Castles in Japan were built to guard important or strategic sites, such a ...
s often have very elaborate moats, with up to three moats laid out in concentric circles around the castle and a host of different patterns engineered around the landscape. The outer moat of a Japanese castle typically protects other support buildings in addition to the castle.
As many Japanese castles have historically been a very central part of their cities, the moats have provided a vital waterway to the city. Even in modern times the moat system of the
Tokyo Imperial Palace
is the main residence of the Emperor of Japan. It is a large park-like area located in the Chiyoda, Chiyoda, Tokyo, Chiyoda district of the Chiyoda, Tokyo, Chiyoda ward of Tokyo and contains several buildings including the where the Emperor h ...
consists of a very active body of water, hosting everything from rental boats and fishing ponds to restaurants.
Most modern Japanese castles have moats filled with water, but castles in the feudal period more commonly had 'dry moats' , a
trench
A trench is a type of digging, excavation or depression in the ground that is generally deeper than it is wide (as opposed to a swale (landform), swale or a bar ditch), and narrow compared with its length (as opposed to a simple hole or trapping ...
. A is a dry moat dug into a slope. A is a series of parallel trenches running up the sides of the excavated mountain, and the earthen wall, which was also called , was an outer wall made of earth dug out from a moat. Even today it is common for mountain Japanese castles to have dry moats. A is a moat filled with water.
Moats were also used in the
Forbidden City
The Forbidden City () is the Chinese Empire, imperial Chinese palace, palace complex in the center of the Imperial City, Beijing, Imperial City in Beijing, China. It was the residence of 24 Ming dynasty, Ming and Qing dynasty, Qing dynasty L ...
and
Xi'an
Xi'an is the list of capitals in China, capital of the Chinese province of Shaanxi. A sub-provincial city on the Guanzhong plain, the city is the third-most populous city in Western China after Chongqing and Chengdu, as well as the most populou ...
in China; in
Vellore Fort in India;
Hsinchu
Hsinchu (, ), officially Hsinchu City, is a city located in northwestern Taiwan. It is the most populous city in Taiwan that is not a special municipality, with estimated 450,655 inhabitants. Hsinchu is a coastal city bordering the Taiwan ...
in
Taiwan
Taiwan, officially the Republic of China (ROC), is a country in East Asia. The main geography of Taiwan, island of Taiwan, also known as ''Formosa'', lies between the East China Sea, East and South China Seas in the northwestern Pacific Ocea ...
; and in Southeast Asia, such as at
Angkor Wat
Angkor Wat (; , "City/Capital of Wat, Temples") is a Buddhism and Hinduism, Hindu-Buddhist temple complex in Cambodia. Located on a site measuring within the ancient Khmer Empire, Khmer capital city of Angkor, it was originally constructed ...
in
Cambodia
Cambodia, officially the Kingdom of Cambodia, is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. It is bordered by Thailand to the northwest, Laos to the north, and Vietnam to the east, and has a coastline ...
;
Mandalay
Mandalay is the second-largest city in Myanmar, after Yangon. It is located on the east bank of the Irrawaddy River, 631 km (392 mi) north of Yangon. In 2014, the city had a population of 1,225,553.
Mandalay was founded in 1857 by Ki ...
in
Myanmar
Myanmar, officially the Republic of the Union of Myanmar; and also referred to as Burma (the official English name until 1989), is a country in northwest Southeast Asia. It is the largest country by area in Mainland Southeast Asia and has ...
;
Chiang Mai
Chiang Mai, sometimes written as Chiengmai or Chiangmai, is the largest city in northern Thailand, the capital of Chiang Mai province and the List of municipalities in Thailand#Largest cities by urban population, second largest city in Thailan ...
in
Thailand
Thailand, officially the Kingdom of Thailand and historically known as Siam (the official name until 1939), is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. With a population of almost 66 million, it spa ...
and
Huế
Huế (formerly Thừa Thiên Huế province) is the southernmost coastal Municipalities of Vietnam, city in the North Central Coast region, the Central Vietnam, Central of Vietnam, approximately in the center of the country. It borders Quảng ...
in
Vietnam
Vietnam, officially the Socialist Republic of Vietnam (SRV), is a country at the eastern edge of mainland Southeast Asia, with an area of about and a population of over 100 million, making it the world's List of countries and depende ...
.
Australia
The only moated fort ever built in Australia was
Fort Lytton in
Brisbane
Brisbane ( ; ) is the List of Australian capital cities, capital and largest city of the States and territories of Australia, state of Queensland and the list of cities in Australia by population, third-most populous city in Australia, with a ...
. As Brisbane was much more vulnerable to attack than either Sydney or Melbourne a series of coastal defences was built throughout
Moreton Bay, Fort Lytton being the largest.
Built between 1880 and 1881 in response to fear of a Russian invasion, it is a pentagonal fortress concealed behind grassy embankments and surrounded by a water-filled moat.
North America
Moats were developed independently by
North America
North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...
n
indigenous people
There is no generally accepted definition of Indigenous peoples, although in the 21st century the focus has been on self-identification, cultural difference from other groups in a state, a special relationship with their traditional territ ...
of the
Mississippian culture
The Mississippian culture was a collection of Native American societies that flourished in what is now the Midwestern, Eastern, and Southeastern United States from approximately 800 to 1600 CE, varying regionally. It was known for building la ...
as the outer defence of some fortified villages. The remains of a 16th-century moat are still visible at the
Parkin Archeological State Park in eastern
Arkansas
Arkansas ( ) is a landlocked state in the West South Central region of the Southern United States. It borders Missouri to the north, Tennessee and Mississippi to the east, Louisiana to the south, Texas to the southwest, and Oklahoma ...
.
The
Maya people
Maya () are an ethnolinguistic group of Indigenous peoples of the Americas, Indigenous peoples of Mesoamerica. The ancient Maya civilization was formed by members of this group, and today's Maya are generally descended from people who lived w ...
also used moats, for example in the city of
Becan.
European colonists in the Americas often built dry ditches surrounding forts built to protect important landmarks, harbours or cities (e.g.
Fort Jay
Fort Jay is a coastal bastion fort and the name of a former United States Army post on Governors Island in New York Harbor, within New York City. Fort Jay is the oldest existing defensive structure on the island, and was named for John Jay, a m ...
on
Governors Island
Governors Island is a island in New York Harbor, within the Boroughs of New York City, New York City borough of Manhattan. It is located approximately south of Manhattan Island, and is separated from Brooklyn to the east by the Buttermilk ...
in
New York Harbor
New York Harbor is a bay that covers all of the Upper Bay. It is at the mouth of the Hudson River near the East River tidal estuary on the East Coast of the United States.
New York Harbor is generally synonymous with Upper New York Bay, ...
).
Photo gallery
Image:Muiderslot september 2007.JPG, Muiderslot, Netherlands
, Terminology of the Low Countries, informally Holland, is a country in Northwestern Europe, with Caribbean Netherlands, overseas territories in the Caribbean. It is the largest of the four constituent countries of the Kingdom of the Nether ...
Image:The moat around Fort Pulaski, Savannah, GA IMG 4673.JPG, Moat surrounding Fort Pulaski National Monument near Savannah
A savanna or savannah is a mixed woodland-grassland (i.e. grassy woodland) biome and ecosystem characterised by the trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach th ...
, Georgia
Georgia most commonly refers to:
* Georgia (country), a country in the South Caucasus
* Georgia (U.S. state), a state in the southeastern United States
Georgia may also refer to:
People and fictional characters
* Georgia (name), a list of pe ...
Image:Keep of Matsumoto Castle.JPG, Matsumoto Castle, a Japanese Castle in Nagano Prefecture
is a Landlocked country, landlocked Prefectures of Japan, prefecture of Japan located in the Chūbu region of Honshu. Nagano Prefecture has a population of 2,007,682 () and has a geographic area of . Nagano Prefecture borders Niigata Prefecture ...
Image:Bodiam-castle-10My8-1197.jpg, Bodiam Castle
Bodiam Castle () is a 14th-century moated castle near Robertsbridge in East Sussex, England. It was built in 1385 by Sir Edward Dalyngrigge, a former knight of Edward III of England, Edward III, with the permission of Richard II of England, R ...
, a 14th-century castle near Robertsbridge in East Sussex
East Sussex is a Ceremonial counties of England, ceremonial county in South East England. It is bordered by Kent to the north-east, West Sussex to the west, Surrey to the north-west, and the English Channel to the south. The largest settlement ...
, England
Image:Caerlaverock Castle from the air.jpg, Caerlaverock Castle, a 13th-century castle in southern Scotland
Image:Sunset of the Forbidden City 2006.JPG, The Forbidden City, Beijing
Beijing, Chinese postal romanization, previously romanized as Peking, is the capital city of China. With more than 22 million residents, it is the world's List of national capitals by population, most populous national capital city as well as ...
: North-western angle
Image: Angkor-Wat-from-the-air.JPG, Angkor Wat
Angkor Wat (; , "City/Capital of Wat, Temples") is a Buddhism and Hinduism, Hindu-Buddhist temple complex in Cambodia. Located on a site measuring within the ancient Khmer Empire, Khmer capital city of Angkor, it was originally constructed ...
, Cambodia
Cambodia, officially the Kingdom of Cambodia, is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. It is bordered by Thailand to the northwest, Laos to the north, and Vietnam to the east, and has a coastline ...
Image:Egeskov Slot 08.jpg, Egeskov Castle, Denmark
Denmark is a Nordic countries, Nordic country in Northern Europe. It is the metropole and most populous constituent of the Kingdom of Denmark,, . also known as the Danish Realm, a constitutionally unitary state that includes the Autonomous a ...
Image:LissingenEugenBracht1880BurgLissingen.jpg, Castle of Lissingen
Image:Sigiriya moat 2011.jpg, Sigiriya
Sigiriya or Sinhagiri (''Lion Rock'' , , pronounced SEE-gi-ri-yə) is an ancient rock fortress located in the northern Matale District near the town of Dambulla in the Central Province, Sri Lanka. It is a site of historical and archaeologic ...
moat, Sri Lanka
Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka, also known historically as Ceylon, is an island country in South Asia. It lies in the Indian Ocean, southwest of the Bay of Bengal, separated from the Indian subcontinent, ...
File:Qufu City Wall - south of the west gate - looking S - P1050985.JPG, Frozen moat of the walled city of Qufu
Qufu ( ; zh, c=曲阜) is a county-level city in southwestern Shandong province, East China. It is located about south of the provincial capital Jinan and northeast of the prefectural seat at Jining. Qufu has an area of 815 square kilometers, ...
, China
Image:Fortbourtange.jpg, Fort Bourtange, a late 16th-century star fort
A bastion fort or ''trace italienne'' (a phrase derived from non-standard French, meaning 'Italian outline') is a fortification in a style developed during the early modern period in response to the ascendancy of gunpowder weapons such as c ...
in Groningen
Groningen ( , ; ; or ) is the capital city and main municipality of Groningen (province), Groningen province in the Netherlands. Dubbed the "capital of the north", Groningen is the largest place as well as the economic and cultural centre of ...
, Netherlands
, Terminology of the Low Countries, informally Holland, is a country in Northwestern Europe, with Caribbean Netherlands, overseas territories in the Caribbean. It is the largest of the four constituent countries of the Kingdom of the Nether ...
Image:Fort Brockhurst 4-Gosport - geograph.org.uk - 693238.jpg, Fort Brockhurst a mid-19th-century polygonal fort in Hampshire
Hampshire (, ; abbreviated to Hants.) is a Ceremonial counties of England, ceremonial county in South East England. It is bordered by Berkshire to the north, Surrey and West Sussex to the east, the Isle of Wight across the Solent to the south, ...
, England
Image:Castello_esterno.jpg, The Castello Estense
The ' ('House of Este, Este castle') or ' ('St. Michael's castle') is a moated medieval castle in the center of Ferrara, northern Italy. It consists of a large block with four corner towers.
History
On 3 May 1385, the Ferrarese people, driven ...
of Ferrara
Ferrara (; ; ) is a city and ''comune'' (municipality) in Emilia-Romagna, Northern Italy, capital of the province of Ferrara. it had 132,009 inhabitants. It is situated northeast of Bologna, on the Po di Volano, a branch channel of the main ...
, Italy
Image:Fort-Jefferson Dry-Tortugas.jpg, Fort Jefferson, Dry Tortugas
Dry Tortugas National Park is a national park of the United States located about west of Key West in the Gulf of Mexico, in the United States. The park preserves Fort Jefferson and the several Dry Tortugas islands, the westernmost and most iso ...
, Florida
Florida ( ; ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders the Gulf of Mexico to the west, Alabama to the northwest, Georgia (U.S. state), Georgia to the north, the Atlantic ...
Image:Moat Castle Steinfurt.jpg, Moat with civic houses bordering on it in Steinfurt
Image:Beijing ancient city gate and moat.jpg, Beijing
Beijing, Chinese postal romanization, previously romanized as Peking, is the capital city of China. With more than 22 million residents, it is the world's List of national capitals by population, most populous national capital city as well as ...
ancient city gate and moat
Image:Vellorefort.jpg, Vellore Fort Moat, in Tamil Nadu
Tamil Nadu (; , TN) is the southernmost States and union territories of India, state of India. The List of states and union territories of India by area, tenth largest Indian state by area and the List of states and union territories of Indi ...
, India
India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area; the List of countries by population (United Nations), most populous country since ...
File:Daalsesingel-Utrecht-2020.jpg, The ''Daalsesingel'', a part of the moat that surrounds the city center of Utrecht
Utrecht ( ; ; ) is the List of cities in the Netherlands by province, fourth-largest city of the Netherlands, as well as the capital and the most populous city of the Provinces of the Netherlands, province of Utrecht (province), Utrecht. The ...
, Netherlands
File:Hikone-Castle-canal-cherry-blossom-2018-Luka-Peternel.jpg, Hikone Castle moat
File:Gate-of-Divine-Might-Forbidden-City-2018-Luka-Peternel.jpg, Forbidden City
The Forbidden City () is the Chinese Empire, imperial Chinese palace, palace complex in the center of the Imperial City, Beijing, Imperial City in Beijing, China. It was the residence of 24 Ming dynasty, Ming and Qing dynasty, Qing dynasty L ...
moat
File:Landskrona citadell från luften.jpg, Landskrona Citadel with mid 15th-century dual moat construction
Modern usage
Architectural usage
Dry moats were a key element used in French
Classicism
Classicism, in the arts, refers generally to a high regard for a classical period, classical antiquity in the Western tradition, as setting standards for taste which the classicists seek to emulate. In its purest form, classicism is an aesthe ...
and
Beaux-Arts architecture
Beaux-Arts architecture ( , ) was the academic architectural style taught at the in Paris, particularly from the 1830s to the end of the 19th century. It drew upon the principles of French neoclassicism, but also incorporated Renaissance and ...
dwellings, both as decorative designs and to provide discreet access for service. Excellent examples of these can be found in Newport, Rhode Island at
Miramar (mansion) and
The Elms, as well as at
Carolands, outside of San Francisco, California, and at
Union Station
A union station, union terminal, joint station, or joint-use station is a railway station at which the tracks and facilities are shared by two or more separate railway company, railway companies, allowing passengers to connect conveniently bet ...
in
Toronto
Toronto ( , locally pronounced or ) is the List of the largest municipalities in Canada by population, most populous city in Canada. It is the capital city of the Provinces and territories of Canada, Canadian province of Ontario. With a p ...
, Ontario, Canada. Additionally, a dry moat can allow light and fresh air to reach basement workspaces, as for example at the
James Farley Post Office in
New York City
New York, often called New York City (NYC), is the most populous city in the United States, located at the southern tip of New York State on one of the world's largest natural harbors. The city comprises five boroughs, each coextensive w ...
.
Anti-terrorist moats
Whilst moats are no longer a significant tool of warfare, modern architectural building design continues to use them as a defence against certain modern threats, such as terrorist attacks from
car bomb
A car bomb, bus bomb, van bomb, lorry bomb, or truck bomb, also known as a vehicle-borne improvised explosive device (VBIED), is an improvised explosive device designed to be detonated in an automobile or other vehicles.
Car bombs can be roug ...
s and
improvised fighting vehicles. For example, the new location of the
Embassy of the United States in London, opened in 2018, includes a moat among its security features - the first moat built in England for more than a century. Modern moats may also be used for aesthetic or ergonomic purposes.
The
Catawba Nuclear Station has a concrete moat around the sides of the plant
not bordering a lake. The moat is a part of precautions added to such sites after the
September 11, 2001 attacks
The September 11 attacks, also known as 9/11, were four coordinated Islamist terrorist suicide attacks by al-Qaeda against the United States in 2001. Nineteen terrorists hijacked four commercial airliners, crashing the first two into ...
.
Safety moats
Moats, rather than fences, separate animals from spectators in many modern
zoo installations. Moats were first used in this way by
Carl Hagenbeck at his
Tierpark in
Hamburg
Hamburg (, ; ), officially the Free and Hanseatic City of Hamburg,. is the List of cities in Germany by population, second-largest city in Germany after Berlin and List of cities in the European Union by population within city limits, 7th-lar ...
, Germany. The structure, with a vertical outer retaining wall rising direct from the moat, is an extended usage of the
ha-ha
A ha-ha ( or ), also known as a sunk fence, blind fence, ditch and fence, deer wall, or foss, is a recessed landscape design element that creates a vertical barrier (particularly on one side) while preserving an uninterrupted view of the lan ...
of English landscape gardening.
Border defence moats
In 2004, plans were suggested for a two-mile moat across the southern border of the
Gaza Strip
The Gaza Strip, also known simply as Gaza, is a small territory located on the eastern coast of the Mediterranean Sea; it is the smaller of the two Palestinian territories, the other being the West Bank, that make up the State of Palestine. I ...
to prevent tunnelling from Egyptian territory to the border town of
Rafah
Rafah ( ) is a city in the southern Gaza Strip, Palestine, and the capital of the Rafah Governorate. It is located south-west of Gaza City. In 2017, Rafah had a population of 171,889. Due to the Gaza war, about 1.4 million people from Gaza C ...
.
In 2008, city officials in
Yuma, Arizona
Yuma is a city in and the county seat of Yuma County, Arizona, United States. The city's population was 95,548 at the 2020 census, up from the 2010 census population of 93,064.
Yuma is the principal city of the Yuma, Arizona, Metropolitan ...
planned to dig out a two-mile stretch of a wetland known as Hunters Hole to control immigrants coming from Mexico.
Pest control moats
Researchers of
jumping spider
Jumping spiders are a group of spiders that constitute the family (biology), family Salticidae. , this family contained over 600 species description, described genus, genera and over 6,000 described species, making it the largest family of spide ...
s, which have excellent vision and adaptable tactics,
built water-filled miniature moats, too wide for the spiders to jump across. Some specimens were rewarded for jumping then swimming and others for swimming only. ''
Portia fimbriata'' from
Queensland
Queensland ( , commonly abbreviated as Qld) is a States and territories of Australia, state in northeastern Australia, and is the second-largest and third-most populous state in Australia. It is bordered by the Northern Territory, South Austr ...
generally succeeded, for whichever method they were rewarded.
When specimens from two different populations of ''
Portia labiata'' were set the same task, members of one population determined which method earned them a reward, whilst members of the other continued to use whichever method they tried first and did not try to adapt.
As a basic method of pest control in
bonsai
Bonsai (; , ) is the Japanese art of Horticulture, growing and shaping miniature trees in containers, with a long documented history of influences and native Japanese development over a thousand years, and with unique aesthetics, cultural hist ...
, a moat may be used to restrict access of crawling insects to the bonsai.
See also
*
Drawbridge
A drawbridge or draw-bridge is a type of moveable bridge typically at the entrance to a castle or tower surrounded by a moat. In some forms of English, including American English, the word ''drawbridge'' commonly refers to all types of moveable b ...
*''
Gracht''
*
Ha-ha
A ha-ha ( or ), also known as a sunk fence, blind fence, ditch and fence, deer wall, or foss, is a recessed landscape design element that creates a vertical barrier (particularly on one side) while preserving an uninterrupted view of the lan ...
wall
*
Moated settlements
A ( ) is a human settlement (village) surrounded by a moat. It is thought to be a new settlement boundary facility brought from the continent along with paddy rice agriculture.
Roots
The roots of the "moat encircling" and "moat shelter" are th ...
*
Moot hill (sometimes written as Moat Hill)
*
Neck ditch
*
Bullengraben
References
External links
{{Authority control
Engineering barrages
Castle architecture
Masonry
Water