Istanbul TF1 Line Symbol

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, postal_code_type = Postal code
, postal_code = 34000 to 34990
, area_code = +90 212 (European side)
+90 216 (Asian side)
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, blank_name = GDP (Nominal)
, blank_info = 2021
, blank1_name =  - Total
, blank1_info = US$ 248 billion
, blank2_name =  - Per capita
, blank2_info = US$ 15,666
, blank3_name = HDI (2019)
, blank3_info = 0.846 (very high) · 1st
, timezone = TRT
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, government_type = Mayor–council government
, governing_body = Municipal Council of Istanbul
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, established_date = 11 May 330 AD
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Istanbul ( , ; tr, İstanbul ), formerly known as Constantinople ( grc-gre, Κωνσταντινούπολις; la, Constantinopolis), is the largest city in Turkey, serving as the country's economic, cultural and historic hub. The city straddles the Bosporus strait, lying in both Europe and Asia, and has a population of over 15 million residents, comprising 19% of the population of Turkey. Istanbul is the most populous European city, and the world's 15th-largest city.

The city was founded as Byzantium ( grc-gre, Βυζάντιον, ) in the 7th century BCE by Greek settlers from Megara. In 330 CE, the Roman emperor Constantine the Great made it his imperial capital, renaming it first as New Rome ( grc-gre, Νέα Ῥώμη, ; la, Nova Roma) and then as Constantinople () after himself. The city grew in size and influence, eventually becoming a beacon of the Silk Road and one of the most important cities in history.

The city served as an imperial capital for almost 1600 years: during the Roman/ Byzantine (330–1204), Latin (1204–1261), late Byzantine (1261–1453), and Ottoman (1453–1922) empires. The city played a key role in the advancement of Christianity during Roman/Byzantine times, hosting four of the first seven ecumenical councils before its transformation to an Islamic stronghold following the Fall of Constantinople in 1453 CE—especially after becoming the seat of the Ottoman Caliphate in 1517. In 1923, after the Turkish War of Independence, Ankara replaced the city as the capital of the newly formed Republic of Turkey. In 1930, the city's name was officially changed to Istanbul, the Turkish rendering of (romanized: ; 'to the City'), the appellation Greek speakers used since the 11th century to colloquially refer to the city.

Over foreign visitors came to Istanbul in 2018, eight years after it was named a European Capital of Culture, making it the world's eighth most visited city. Istanbul is home to several UNESCO World Heritage Sites, and hosts the headquarters of numerous Turkish companies, accounting for more than thirty percent of the country's economy.

Toponymy

The first known name of the city is ''Byzantium'' ( grc-gre, Βυζάντιον, ), the name given to it at its foundation by Megarian colonists around 657 BCE. Megarian colonists claimed a direct line back to the founders of the city, Byzas, the son of the god Poseidon and the nymph Ceroëssa. Modern excavations have raised the possibility that the name Byzantium might reflect the sites of native Thracian settlements that preceded the fully-fledged town. Constantinople comes from the Latin name Constantinus, after Constantine the Great, the Roman emperor who refounded the city in 324 CE. Constantinople remained the most common name for the city in the West until the 1930s, when Turkish authorities began to press for the use of "Istanbul" in foreign languages. ( ota, قسطنطينيه) and were the names used alternatively by the Ottomans during their rule.

The name (, colloquially ) is commonly held to derive from the Medieval Greek phrase (pronounced ), which means "to the city" and is how Constantinople was referred to by the local Greeks. This reflected its status as the only major city in the vicinity. The importance of Constantinople in the Ottoman world was also reflected by its nickname meaning the 'Gate to Prosperity' in Ottoman Turkish. An alternative view is that the name evolved directly from the name ''Constantinople'', with the first and third syllables dropped. Some Ottoman sources of the 17th century, such as Evliya Çelebi, describe it as the common Turkish name of the time; between the late 17th and late 18th centuries, it was also in official use. The first use of the word ( ota, اسلامبول) on coinage was in 1730 during the reign of Sultan Mahmud I. In modern Turkish, the name is written as , with a dotted İ, as the Turkish alphabet distinguishes between a dotted and dotless I. In English the stress is on the first or last syllable, but in Turkish it is on the second syllable (). A person from the city is an (plural: ); ''Istanbulite'' is used in English.

History

Neolithic artifacts, uncovered by archeologists at the beginning of the 21st century, indicate that Istanbul's historic peninsula was settled as far back as the 6th millennium BCE. That early settlement, important in the spread of the Neolithic Revolution from the Near East to Europe, lasted for almost a millennium before being inundated by rising water levels. The first human settlement on the Asian side, the Fikirtepe mound, is from the Copper Age period, with artifacts dating from 5500 to 3500 BCE, On the European side, near the point of the peninsula ( Sarayburnu), there was a Thracian settlement during the early 1st millennium BCE. Modern authors have linked it to the Thracian toponym ''Lygos'', mentioned by Pliny the Elder as an earlier name for the site of Byzantium.

The history of the city proper begins around 660 BCE, when Greek settlers from Megara established Byzantium on the European side of the Bosporus. The settlers built an acropolis adjacent to the Golden Horn on the site of the early Thracian settlements, fueling the nascent city's economy. The city experienced a brief period of Persian rule at the turn of the 5th century BCE, but the Greeks recaptured it during the Greco-Persian Wars. Byzantium then continued as part of the Athenian League and its successor, the Second Athenian League, before gaining independence in 355 BCE. Long allied with the Romans, Byzantium officially became a part of the Roman Empire in 73 CE. Byzantium's decision to side with the Roman usurper Pescennius Niger against Emperor Septimius Severus cost it dearly; by the time it surrendered at the end of 195 CE, two years of siege had left the city devastated. Five years later, Severus began to rebuild Byzantium, and the city regained—and, by some accounts, surpassed—its previous prosperity.

Rise and fall of Constantinople and the Byzantine Empire

Constantine the Great effectively became the emperor of the whole of the Roman Empire in September 324. Two months later, he laid out the plans for a new, Christian city to replace Byzantium. As the eastern capital of the empire, the city was named '' Nova Roma''; most called it Constantinople, a name that persisted into the 20th century. On 11 May 330, Constantinople was proclaimed the capital of the Roman Empire, which was later permanently divided between the two sons of Theodosius I upon his death on 17 January 395, when the city became the capital of the Eastern Roman (Byzantine) Empire.

The establishment of Constantinople was one of Constantine's most lasting accomplishments, shifting Roman power eastward as the city became a center of Greek culture and Christianity. Numerous churches were built across the city, including Hagia Sophia which was built during the reign of Justinian the Great and remained the world's largest cathedral for a thousand years. Constantine also undertook a major renovation and expansion of the Hippodrome of Constantinople; accommodating tens of thousands of spectators, the hippodrome became central to civic life and, in the 5th and 6th centuries, the center of episodes of unrest, including the Nika riots. Constantinople's location also ensured its existence would stand the test of time; for many centuries, its walls and seafront protected Europe against invaders from the east and the advance of Islam. During most of the Middle Ages, the latter part of the Byzantine era, Constantinople was the largest and wealthiest city on the European continent and at times the largest in the world. Constantinople is generally considered to be the center and the "cradle of Orthodox Christian civilization".

Constantinople began to decline continuously after the end of the reign of Basil II in 1025. The Fourth Crusade was diverted from its purpose in 1204, and the city was sacked and pillaged by the crusaders. They established the Latin Empire in place of the Orthodox Byzantine Empire. Hagia Sophia was converted to a Catholic church in 1204. The Byzantine Empire was restored, albeit weakened, in 1261. Constantinople's churches, defenses, and basic services were in disrepair, and its population had dwindled to a hundred thousand from half a million during the 8th century. After the reconquest of 1261, however, some of the city's monuments were restored, and some, like the two Deesis mosaics in Hagia Sophia and Kariye, were created.

Various economic and military policies instituted by Andronikos II, such as the reduction of military forces, weakened the empire and left it vulnerable to attack. In the mid-14th-century, the Ottoman Turks began a strategy of gradually taking smaller towns and cities, cutting off Constantinople's supply routes and strangling it slowly. On 29 May 1453, after an eight-week siege (during which the last Roman emperor, Constantine XI, was killed), Sultan Mehmed II "the Conqueror" captured Constantinople and declared it the new capital of the Ottoman Empire. Hours later, the sultan rode to the Hagia Sophia and summoned an imam to proclaim the Islamic creed, converting the grand cathedral into an imperial mosque due to the city's refusal to surrender peacefully. Mehmed declared himself as the new '' Kayser-i Rûm'' (the Ottoman Turkish equivalent of the Caesar of Rome) and the Ottoman state was reorganized into an empire.

Ottoman Empire and Turkish Republic eras

Following the conquest of Constantinople, Mehmed II immediately set out to revitalize the city. Cognizant that revitalization would fail without the repopulation of the city, Mehmed II welcomed everyone–foreigners, criminals, and runaways– showing extraordinary openness and willingness to incorporate outsiders that came to define Ottoman political culture. He also invited people from all over Europe to his capital, creating a cosmopolitan society that persisted through much of the Ottoman period. Revitalizing Istanbul also required a massive program of restorations, of everything from roads to aqueducts. Like many monarchs before and since, Mehmed II transformed Istanbul's urban landscape with wholesale redevelopment of the city center. There was a huge new palace to rival, if not overshadow, the old one, a new covered market (still standing as the Grand Bazaar), porticoes, pavilions, walkways, as well as more than a dozen new mosques. Mehmed II turned the ramshackle old town into something that looked like an imperial capital.

Social hierarchy was ignored by the rampant plague, which killed the rich and the poor alike in the 16th century. Money could not protect the rich from all the discomforts and harsher sides of Istanbul. Although the Sultan lived at a safe remove from the masses, and the wealthy and poor tended to live side by side, for the most part Istanbul was not zoned as modern cities are. Opulent houses shared the same streets and districts with tiny hovels. Those rich enough to have secluded country properties had a chance of escaping the periodic epidemics of sickness that blighted Istanbul.

The Ottoman Dynasty claimed the status of caliphate in 1517, with Constantinople remaining the capital of this last caliphate for four centuries. Suleiman the Magnificent's reign from 1520 to 1566 was a period of especially great artistic and architectural achievement; chief architect Mimar Sinan designed several iconic buildings in the city, while Ottoman arts of ceramics, stained glass, calligraphy, and miniature flourished. The population of Constantinople was 570,000 by the end of the 18th century.

A period of rebellion at the start of the 19th century led to the rise of the progressive Sultan Mahmud II and eventually to the ''Tanzimat'' period, which produced political reforms and allowed new technology to be introduced to the city. Bridges across the Golden Horn were constructed during this period, and Constantinople was connected to the rest of the European railway network in the 1880s. Modern facilities, such as a water supply network, electricity, telephones, and trams, were gradually introduced to Constantinople over the following decades, although later than to other European cities. The modernization efforts were not enough to forestall the decline of the Ottoman Empire.

Sultan Abdul Hamid II was deposed with the Young Turk Revolution in 1908 and the Ottoman Parliament, closed since 14 February 1878, was reopened 30 years later on 23 July 1908, which marked the beginning of the Second Constitutional Era. A series of wars in the early 20th century, such as the Italo-Turkish War (1911–1912) and the Balkan Wars (1912–1913), plagued the ailing empire's capital and resulted in the 1913 Ottoman coup d'état, which brought the regime of the Three Pashas.

The Ottoman Empire joined World War I (1914–1918) on the side of the Central Powers and was ultimately defeated. The deportation of Armenian intellectuals on 24 April 1915 was among the major events which marked the start of the Armenian genocide during WWI. Due to Ottoman and Turkish policies of Turkification and ethnic cleansing, the city's Christian population declined from 450,000 to 240,000 between 1914 and 1927. The Armistice of Mudros was signed on 30 October 1918 and the Allies occupied Constantinople on 13 November 1918. The Ottoman Parliament was dissolved by the Allies on 11 April 1920 and the Ottoman delegation led by Damat Ferid Pasha was forced to sign the Treaty of Sèvres on 10 August 1920.

Following the Turkish War of Independence (1919–1922), the Grand National Assembly of Turkey in Ankara abolished the Sultanate on 1 November 1922, and the last Ottoman Sultan, Mehmed VI, was declared ''persona non grata''. Leaving aboard the British warship HMS ''Malaya'' on 17 November 1922, he went into exile and died in Sanremo, Italy, on 16 May 1926. The Treaty of Lausanne was signed on 24 July 1923, and the occupation of Constantinople ended with the departure of the last forces of the Allies from the city on 4 October 1923. Turkish forces of the Ankara government, commanded by Şükrü Naili Pasha (3rd Corps), entered the city with a ceremony on 6 October 1923, which has been marked as the ''Liberation Day'' of Istanbul (Turkish: ''İstanbul'un Kurtuluşu'') and is commemorated every year on its anniversary. On 29 October 1923 the Grand National Assembly of Turkey declared the establishment of the Turkish Republic, with Ankara as its capital. Mustafa Kemal Atatürk became the Republic's first President.

A 1942 wealth tax assessed mainly on non-Muslims led to the transfer or liquidation of many businesses owned by religious minorities. From the late 1940s and early 1950s, Istanbul underwent great structural change, as new public squares, boulevards, and avenues were constructed throughout the city, sometimes at the expense of historical buildings. The population of Istanbul began to rapidly increase in the 1970s, as people from Anatolia migrated to the city to find employment in the many new factories that were built on the outskirts of the sprawling metropolis. This sudden, sharp rise in the city's population caused a large demand for housing, and many previously outlying villages and forests became engulfed into the metropolitan area of Istanbul.

Geography

Istanbul is located in north-western Turkey and straddles the strait Bosporus, which provides the only passage from the Black Sea to the Mediterranean via the Sea of Marmara. Historically, the city has been ideally situated for trade and defense: The confluence of the Sea of Marmara, the Bosporus, and the Golden Horn provide both ideal defense against enemy attack and a natural toll-gate. Several picturesque islands— Büyükada, Heybeliada, Burgazada, Kınalıada, and five smaller islands—are part of the city. Istanbul's shoreline has grown beyond its natural limits. Large sections of Caddebostan sit on areas of landfill, increasing the total area of the city to .

Despite the myth that seven hills make up the city, there are, in fact, more than 50 hills within the city limits. Istanbul's tallest hill, Aydos, is high.

The nearby North Anatolian Fault is responsible for much earthquake activity, although it doesn't physically pass through the city itself, and a quake of at least magnitude 7 is more likely than not before 2030 and very likely in the 21st century. The fault caused the earthquakes in 1766 and 1894. The threat of major earthquakes plays a large role in the city's infrastructure development, with over 500,000 vulnerable buildings demolished and replaced since 2012. The city has repeatedly upgraded its building codes, most recently in 2018, requiring retrofits for older buildings and higher engineering standards for new construction.

Climate

Istanbul has a borderline Mediterranean climate ( Köppen ''Csa'', Trewartha ''Cs''), humid subtropical climate (Köppen ''Cfa'', Trewartha ''Cf'') and oceanic climate (Köppen ''Cfb'', Trewartha ''Do'') under both classifications. It experiences cool winters with frequent precipitation, and warm to hot (mean temperature peaking at to in August, depending on location), moderately dry summers. Spring and fall are usually mild, with varying conditions dependent on wind direction.

Istanbul's weather is strongly influenced by the Sea of Marmara to the south, and the Black Sea to the north. This moderates temperature swings and produces a mild temperate climate with low diurnal temperature variation. Consequently, Istanbul's temperatures almost always oscillate between and , and most of the city does not experience temperatures above for more than 14 days a year. Another effect of Istanbul's maritime position is its persistently high dew points, near-saturation morning humidity, and frequent fog, which also limits Istanbul's sunshine hours to levels closer to Western Europe, and gives the city its noticeable seasonal lag; Istanbul is one of the few cities in the temperate Northern Hemisphere where March is, on average, colder than December.

Because of its hilly topography and maritime influences, Istanbul exhibits a multitude of distinct microclimates. Within the city, rainfall varies widely owing to the rain shadow of the hills in Istanbul, from around on the southern fringe at Florya to on the northern fringe at Bahçeköy. Furthermore, while the city itself lies in USDA hardiness zones 9a to 9b, its inland suburbs lie in zone 8b with isolated pockets of zone 8a, restricting the cultivation of cold-hardy subtropical plants to the coasts.

As Istanbul is only slightly rain shadowed from Mediterranean storms and is otherwise surrounded by water, it usually receives some amount of precipitation from both Western European and Mediterranean systems. This results in frequent precipitation: the average number of rainy days in the city is 131, and in some parts it may reach up to 152 days. Furthermore, during early and mid-winter, the city's frequency of precipitation is virtually unparalleled in the Mediterranean basin; January averages 20 days of precipitation when counting trace accumulations, 17 when using a 0.1 mm threshold, and 12 when using a 1.0 mm threshold.

The highest recorded temperature at the official downtown observation station in Sarıyer was and on 13 July 2000. The lowest recorded temperature was on 9 February 1929. The highest recorded snow cover in the city center was on 4 January 1942, and in the northern suburbs on 11 January 2017.

Climate change

As with virtually every part of the world, climate change is causing more heatwaves, droughts, storms, and flooding in Istanbul. Furthermore, as Istanbul is a large and rapidly expanding city, its urban heat island has been intensifying the effects of climate change. Considering past data, it is very likely that these two factors are responsible for urban Istanbul's shift, from a warm-summer climate to a hot-summer one in the Köppen climate classification, and from the cool temperate zone to the warm temperate/subtropical zone in the Trewartha climate classification. If trends continue, sea level rise is likely to affect city infrastructure, for example Kadıkoy metro station is threatened with flooding.
Xeriscaping of green spaces has been suggested, and Istanbul has a climate-change action plan.

Cityscape

Districts and neighborhoods

European side

The Fatih district, which was named after Sultan Mehmed II (Turkish: ''Fatih Sultan Mehmed''), corresponds to what was, until the Ottoman conquest in 1453, the whole of the city of Constantinople (today is the capital district and called the ''historic peninsula'' of Istanbul) on the southern shore of the Golden Horn, across the medieval Genoese citadel of Galata on the northern shore. The Genoese fortifications in Galata were largely demolished in the 19th century, leaving only the Galata Tower, to make way for the northward expansion of the city. Galata ( Karaköy) is today a quarter within the Beyoğlu (Pera) district, which forms Istanbul's commercial and entertainment center and includes İstiklal Avenue and Taksim Square.

Dolmabahçe Palace, the seat of government during the late Ottoman period, is in the Beşiktaş district on the European shore of the Bosporus strait, to the north of Beyoğlu. The former village of Ortaköy is within Beşiktaş and gives its name to the Ortaköy Mosque on the Bosporus, near the Bosporus Bridge. Lining both the European and Asian shores of the Bosporus are the historic '' yalıs'', luxurious chalet mansions built by Ottoman aristocrats and elites as summer homes. Inland, north of Taksim Square is the Istanbul Central Business District, a set of corridors lined with office buildings, residential towers, shopping centers, and university campuses, and over of class-A office space in total. Maslak, Levent, and Bomonti are important nodes within the CBD.

The Atatürk Airport corridor is another such edge city-style business, residential and shopping corridor with over of class-A office space.

Asian side

During the Ottoman period, Üsküdar (then Scutari) and Kadıköy were outside the scope of the urban area, serving as tranquil outposts with seaside ''yalıs'' and gardens. But in the second half of the 20th century, the Asian side experienced major urban growth; the late development of this part of the city led to better infrastructure and tidier urban planning when compared with most other residential areas in the city. Much of the Asian side of the Bosporus functions as a suburb of the economic and commercial centers in European Istanbul, accounting for a third of the city's population but only a quarter of its employment. However, Kozyatağı–Ataşehir, Altunizade, Kavacık and Ümraniye, all together having around 1.4 million sqm of class-A office space) are now important "edge cities", i.e. corridors and nodes of business and shopping centers and of tall residential buildings.

Expansion

As a result of Istanbul's exponential growth in the 20th century, a significant portion of the city is composed of '' gecekondus'' (literally "built overnight"), referring to illegally constructed squatter buildings. At present, some ''gecekondu'' areas are being gradually demolished and replaced by modern mass-housing compounds. Moreover, large scale gentrification and urban renewal projects have been taking place, such as the one in Tarlabaşı; some of these projects, like the one in Sulukule, have faced criticism. The Turkish government also has ambitious plans for an expansion of the city west and northwards on the European side in conjunction with the new Istanbul Airport, opened in 2019; the new parts of the city will include four different settlements with specified urban functions, housing 1.5 million people.

Parks

Istanbul does not have a primary urban park, but it has several green areas. Gülhane Park and Yıldız Park were originally included within the grounds of two of Istanbul's palaces — Topkapı Palace and Yıldız Palace—but they were repurposed as public parks in the early decades of the Turkish Republic. Another park, Fethi Paşa Korusu, is on a hillside adjacent to the Bosphorus Bridge in Anatolia, opposite Yıldız Palace in Europe. Along the European side, and close to the Fatih Sultan Mehmet Bridge, is Emirgan Park, which was known as the ''Kyparades'' (Cypress Forest) during the Byzantine period. In the Ottoman period, it was first granted to Nişancı Feridun Ahmed Bey in the 16th century, before being granted by Sultan Murad IV to the Safavid Emir Gûne Han in the 17th century, hence the name ''Emirgan''. The park was later owned by Khedive Ismail Pasha of Ottoman Egypt and Sudan in the 19th century. Emirgan Park is known for its diversity of plants and an annual tulip festival is held there since 2005. The AKP government's decision to replace Taksim Gezi Park with a replica of the Ottoman era Taksim Military Barracks (which was transformed into the Taksim Stadium in 1921, before being demolished in 1940 for building Gezi Park) sparked a series of nationwide protests in 2013 covering a wide range of issues. Popular during the summer among Istanbulites is Belgrad Forest, spreading across at the northern edge of the city. The forest originally supplied water to the city and remnants of reservoirs used during Byzantine and Ottoman times survive.

Architecture

Istanbul is primarily known for its Byzantine and Ottoman architecture. Despite its development as a Turkish city since 1453, it contains many ancient, Roman, Byzantine, Christian, Muslim, and Jewish monuments.

The Neolithic settlement in the Yenikapı quarter on the European side, which dates back to c. 6500 BCE and predates the formation of the Bosporus strait by approximately a millennium (when the Sea of Marmara was still a lake) was discovered during the construction of the Marmaray railway tunnel. It is the oldest known human settlement on the European side of the city. The oldest known human settlement on the Asian side is the Fikirtepe Mound near Kadıköy, with relics dating to c. 5500-3500 BCE ( Chalcolithic period).

There are numerous ancient monuments in the city. The most ancient is the Obelisk of Thutmose III ( Obelisk of Theodosius). Built of red granite, 31 m (100 ft) high, it came from the Temple of Karnak in Luxor, and was erected there by Pharaoh Thutmose III (r. 1479–1425 BCE) to the south of the seventh pylon. The Roman emperor Constantius II (r. 337–361 CE) had it and another obelisk transported along the River Nile to Alexandria for commemorating his ''ventennalia'' or 20 years on the throne in 357. The other obelisk was erected on the '' spina'' of the Circus Maximus in Rome in the autumn of that year, and is now known as the Lateran Obelisk. The obelisk that would become the ''Obelisk of Theodosius'' remained in Alexandria until 390 CE, when Theodosius I (r. 379–395 CE) had it transported to Constantinople and put up on the ''spina'' of the Hippodrome there. Labib Habachi, ''The Obelisks of Egypt, skyscrapers of the past'', American University in Cairo Press, 1985, p.145-151. When re-erected at the Hippodrome of Constantinople, the obelisk was mounted on a decorative base, with reliefs that depict Theodosius I and his courtiers. The lower part of the obelisk was damaged in antiquity, probably during its transport to Alexandria in 357 CE or during its re-erection at the Hippodrome of Constantinople in 390 CE. As a result, the current height of the obelisk is only 18.54 meters, or 25.6 meters if the base is included. Between the four corners of the obelisk and the pedestal are four bronze cubes, used in its transportation and re-erection.E.A. Wallis Budge, ''Cleopatra's Needles and Other Egyptian Obelisks'', The Religious Tract Society, London, 1926, reprinted 1990, p.160-165.

Next in age is the Serpent Column, from 479 BCE. It was brought from