Dardanelles is a 61 kilometer (28 mile) long and from 1.2 to 6.4 km (3/4 to 4 miles) wide strait between Europe and Asiatic Turkey, respectively known as Thrace and Anatolia. This strategically important strait is the Dardanelles. It leads from the Aegean Sea to the Sea of Marmara and then through the Bosphorus strait to the Black Sea. Thus the Dardanelles is the outer gateway to a great productive area. The world's ships must pass through here to reach the grain ports of Ukraine and the oil ports of Romania and the Caucasus region. The western side of the strait is formed by the Gallipoli peninsula. Major ports along its shores are Gallipoli, Eceabat, and Canakkale; and many famous castles like Kilitbahir built in 1452 by the Ottoman sultan Mehmet II, stand along its banks. Also, famous Turkish sailor and the first Turkish marine cartographer Piri Reis was born in Gelibolu town.

The strait is rich with history and legend. In ancient times it was called the Hellespont, meaning "Helle's sea," in memory of Helle, a mythical Boetian princess. She was drowned in its swift waters after falling from the back of the legendary ram with the golden fleece. Across the Hellespont from the eastern side, Leander swam nightly to visit Hera, a priestess of Aphrodite. In 480 BC Persia's king Xerxes sent his army across the strait on a bridge of boats to invade Greece. In 334 BC Alexander the Great similarly crossed from Greece to invade Persia. The strait takes its name from the old town of Dardanus.

Ottomans first put their feet into Gelibolu in 1354 under the reign of Orhan Gazi. But as its center and the region, Canakkale passed completely into Turks in 1362 under the reign of Murat I. In later years Turkish control was supported by British diplomacy, which sought to bar Russia from the Mediterranean. But in World War I, Turkey was allied with Germany. The British, wanting to get aid to Russia through the Black Sea, tried to capture the Gallipoli peninsula in 1915-16. They were thrown back by the Turkish Army under the command of Ataturk and the Dardanelles remained unconquered.

After Turkey's defeat in 1917, the Dardanelles became part of a neutral zone of straits, which was under control of the League of Nations. In 1923 the Treaty of Lausanne returned the region to Turkey. At first, Turkey was denied the right to fortify the straits, but in 1936 another treaty restored this right and also permitted Turkey to close the straits to belligerent ships in wartime.

Since Turkey was neutral until the closing days of World War II, the Dardanelles route to the Soviet Union was closed to Great Britain and the United States. With this sea route barred, the Allies were forced to build roads through Iran to get supplies to the Soviets. The Soviet Union became determined to gain partial control of the Dardanelles after the war. Turkey refused formal demands for a share in the control in 1946 and again in 1947. As the threat of Soviet aggression increased during the Cold War, the United States and Britain encouraged Turkey to stand firm on sole control.

Today, Dardanelles is full of shipwrecks from Gallipoli Campaign which makes divers to have a special interest on this waters. There are also several tours visiting this interesting area, especially to nearby Troy.