İstanbul’s only real river is the Bayrampaşa Creek, which used to be known as Lykos but acquired its other name during the Turkish period.
This creek, after running through the low-lying land between the Fatih and Çapa districts (now Vatan Caddesi), turned towards the sea at Aksaray and flowed into it in the Langa beighbourhood.
There is no trace of this creek today.
However, the water that until recent years, accumulated during the winter in the area of Vatan Caddesi was undoubtedly connected with this creek. Although there is no large source of water within the city, the two shores of the İstanbul strait provide valuable water resources in terms of quality. These springs have been polluted in recent years by the houses and shanty towns that have been built around them. They have been famous throughout history for their taste and other properties and were much sought-after.
The streams outside the city, and the woods and pastures on their banks were popular places for picnics and excursions after the arrival of the Turks. Among these were Kâğıthane, Büyükdere, Göksu, Küçüksu, Çırpıcı, Haydarpaşa and Kurbağalıdere. Due to the fact, that during the past fifty years excursions in decorative boats along these streams and merrymaking on their grassy banks have become a thing of the past. These former beauty spots have become neglected, and because of the various buildings that have been constructed on them, almost all of these natural parks have either disappeared or have become unapproachable because of the waist deposited there. The Kâğıthane Creek, where at one time the magnificent Saadabat (afterwards known as Çağlayan) summer-house and a number of other villas lay, now constitutes a danger for the surrounding neighborhoods due to its filthy and neglected state, and at the same time silts up the bed of the Golden Horn. The foul odor detectable around Kurbağalıdere during the summer months is another example of this problem. This stream, which is now entirely silted up, could until recently be navigated by lighters and small sailing boats as far up as Gazhane.