İETT
Public transport in Istanbul comprises a bus network, various rail systems, funiculars, and maritime services to serve the more than 13 million inhabitants of the city spread over an area of 5712 km².
Public road transport in Istanbul dates back to 30 August 1869, when a contract to build a tram system in the capital of the Ottoman Empire was signed. With this agreement, Konstantin Krepano Efendi’s "Société des Tramways de Constantinople" obtained the concession to operate public transportation for forty years. The inauguration of four lines of horse-driven trams was in 1871. In the first year, the horsecars transported 4.5 million people on the lines Azapkapı-Galata, Aksaray-Yedikule, Aksaray-Topkapı and Eminönü-Aksaray. More lines were added in the following years. 430 horses were used to draw the 45 carriages, including 15 summer-type and some double-deckers, on 1,000 mm (3 ft 3 3⁄8 in) metre gauge track. In 1912, the horse-drawn tram had to cease to operate for one year because the Ministry of Defence sent all the horses to the front during the Balkan War. The tram network was electrified by overhead contact wire on 2 February 1914. The tram began to run on the Anatolian part of Istanbul on 8 June 1928 between Üsküdar and Kısıklı. By the 1950s, the length of the tram lines reached 130 km (81 mi). The trams were on service on the European side of the city until 12 August 1961 and on the Asian side until 14 November 1966.
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