a small but densely populated region to the south of the Caucasus Mountains. It includes three independent states: Georgia in the northwest, Azerbaijan in the east, and Armenia, situated largely on a high mountainous plateau south of Georgia and west of Azerbaijan. Together these countries have an area of about 71,850 square miles (186,100 square kilometres). Transcaucasia, also known as Southern Caucasia, is bounded on the north by Russia, on the east by the Caspian Sea, on the south by Iran and Turkey, and on the west by the Black Sea.
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