Black Sea–Caspian Steppe The Manych Depression is not much more than 65 feet above sea level and the area around Astrakhan and part of Kalmykia is below sea level. Rivers: Through the center runs the northwest-tending Kuma-Manych Depression. This was once a strait connecting the Black and Caspian Seas and is now marked by the Manych River which is basically a chain of lakes. It will probably be the route of the Eurasia Canal if that great engineering work is ever built. In the south the rivers that flow north from the Caucasus are caught by the west-flowing Kuban River and the east-flowing
Black Sea by some scholars such as Marija Gimbutas; others move the heartland further east towards the Caspian Sea, yet others to Anatolia. The Black Sea became an Ottoman Navy lake within five years of Genoa losing the Crimea in 1479, after which the only Western merchant vessels to sail its waters were those of Venice's old rival Ragusa. This restriction was gradually changed by the Russian Navy from 1783 until the relaxation of export controls in 1789 because of the French Revolution. The Black Sea was a significant naval theatre of World War I and saw both naval and land battles