Dardanelles, four castles or forts situated on the opposite shores of the Hellespont, or strait of the Dardanelles, which joins the archipelago (the AEgean sea of the ancients) to the sea of Marmora (Propontis), and extends in a S. W. direction about 45 m., between lat. 40° and 40° 30' N, and lon. 26° 10' and 26° 45' E. The name is probably from the ancient city of Dardanus, on the E. shore. The Dardanelles are intended to command the access to Constantinople, but in several instances ships of war have passed them without serious injury. Thus in 1770 a Russian squadron under Admiral Elphinstone, in 1801 Commodore Bain-bridge in the American frigate George Washington, and in 1807 the British admiral Duckworth, sailed through the strait. The two castles at the entrance from the archipelago, Kum Kale or Hissar Sultani on the Asiatic and Sed-il-Bahr on the European shore, were built by Mohammed IV. in 1659, to secure his fleet against the Venetians, who used to attack it in sight of the old castles; they are in good repair, but inefficient in consequence of the width of the channel (4 3/4 m.). The two old castles, Tchanak Kalesi or Kale Sultanieh in Asia, and Kilid Bahr in Europe, command the strait at a point where it is only 800 yards across, and may be closed by chains.
The principal defences on the European side are two excellent coast batteries, Namasyah and Degermen Burun. All the forts are defended by guns of the largest calibre and of the most modern construction; the bastions are open at the gorge, the batteries without casemates, and both are commanded by hills in the rear. The barrow of Hecuba or Cynossema, where the Athenians erected a trophy after their victory in the Peloponnesian war (411 B. C), is close to the old European castle. The town of Tchanak Kalesi is an indifferent place, containing about 2,000 houses. N. and E. from it a low strip of land called Nagara Burun projects into the sea. This spot has been fixed upon as the site of the ancient Abydos, and a similar projecting point corresponds to it on the European shore. Here Xerxes is supposed to have built his bridge uniting the two continents; here Alexander the Great crossed into Asia; and here the crescent was for the second time planted on European soil by Soly-man (1357). Here also Leander swam across the strait from Abydos to Sestos, to visit Hero, and Lord Byron and Lieut. Eckenhead swam the same distance in 70 minutes (March 3, 1810). The Turkish government has always maintained that no foreign vessel of war should be allowed at any time to pass the Dardanelles, which principle England recognized in 1809; and hence in the Egyptian war of 1832-3 the British and French fleets were not permitted to enter the strait, though a Russian fleet from the Black sea was anchored in the Bosporus. In 1841 the five great powers of Europe fully recognized this principle, and it was reaffirmed by the treaty of Paris in 1856. But in November, 1858, the United States frigate Wabash passed the Dardanelles and anchored at Constantinople, the commanding officer maintaining that the United States, being no party to the treaty of Paris, were not bound by its stipulations.
Without acknowledging explicitly the correctness of this position, the Turkish government received the Wabash in a friendly spirit. In 1870 this clause of the treaty of Paris was abrogated, and there is no longer any restriction on the navigation of the strait. - The so-called Lesser Dardanelles are two large castles situated on Capes Rhion and Antirrhion, at the entrance to the gulf of Le-panto or of Corinth.