the straits between Europe and Asia Minor, which connect the Sea of Marmara with the Aegean Sea.
The Dardanelles originated as a river valley that became inundated by the sea as a result of the land’s subsidence. Length, 120.5 km; width, 1.3–18.5 km; depth. 53–106 m. The banks of the Dardanelles are composed of sandstones and limestones, covered with sparse vegetation. The water exchange through the Dardanelles is determined by the difference in the water densities of the two adjoining seas. The surface current, flowing from the Sea of Marmara in the northeast toward the southwest, carries fresher, less dense waters (with a salinity of between 25.5 and 29.0 parts per thousand and a density of 1.018). The velocity of this current ranges from 2 to 6 km per hr. A deep current flows from the southwest to the northeast and carries from the Aegean Sea saline (up to 38.5 parts per thousand) and dense (1.028–1.029) water. The port of Gelibolu (Gallipoli) is located on the European bank of the Dardanelles, and that of Çanakkale is on the Asian side.