Ustra Fortress
Bulgaria · Europe
About
Ustra (Bulgarian: Устра) is a medieval fortress in the eastern Rhodope Mountains in southern Bulgaria. It is among the highest and best preserved fortifications in the mountain range. The fortress was controlled by the Byzantine and the Bulgarian Empires until the region was conquered by the Ottoman Turks in the second half of the 14th century.
Ustra Peak on Livingston Island in the South Shetland Islands, Antarctica is named after the fortress.
Adapted from Wikipedia (CC BY-SA)。Photography via Wikimedia Commons.