The location of Istanbul is remarkable because the city has exits immediately to the two seas, Marble and Black . But if the coast of the first of them belongs to the city line, then to the Black Sea beaches are so easy not to get . The whole point is that Istanbul is comfortably located on the banks of the Bosphorus, in Turkey called the Istanbul Strait (İstanbul Boğazı) . It connects the shallow and therefore warm Marmara Sea (in Turkish Marmara Denizi ) with Black (for the Turks Karadeniz), whose coast is approximately in 25 km to the north of the city . Water excursions to local courts are regularly sent to the local area on the spill .