Ada Kaleh

Ada Kaleh (Romanian pronunciation: [ˈada kaˈle] from Turkish: Adakale meaning "Island Fortress", Hungarian: Újorsova or Ada Kaleh, Serbian and Bulgarian: Адакале / Adakale) was a small island on the Danube populated mostly by Turks that was submerged during the construction of the Iron Gates hydroelectric plant in 1970. The island was about 3 km downstream from Orşova and measured 1.75 by 0.4–0.5 km.

The isle of Ada Kaleh is probably the most evocative victim of the Iron Gate dam's construction. Once an Ottoman Turkish exclave, it had a mosque and numerous twisting alleys, and was known as a free port and a smuggler's nest.

The Habsburg Monarchy built a Vauban-type fort there to defend it from the Ottoman Empire, and that fort would remain a bone of contention for the two empires. In 1699 the island came under Ottoman control, however, it was recaptured by the Austrians in the 1716–18 war, and the fortress of New Orșova was built by Austrian colonel Nicolas Doxat. After a four-month siege in 1738 it became Ottoman again, followed by the Austrians re-conquering it in 1789, but they had to return the island with the Treaty of Sistova (1791), which ended the 1787–91 war between the Ottoman Empire and the Habsburg Monarchy (and, by extension, the Ottoman–Habsburg wars). Thereafter, the island lost its military importance.

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