Caspian Sea the east often changed course to empty into the Caspian through a now-desiccated riverbed called the Uzboy River, as did the Syr Darya farther north. The Caspian also has several small islands; they are primarily located in the north and have a collective land area of roughly . Adjacent to the North Caspian is the Caspian Depression, a low-lying region below sea level. The Central Asian steppes stretch across the northeast coast, while the Caucasus mountains hug the western shore. The biomes to both the north and east are characterized by cold, continental deserts. Conversely, the climate to the southwest
Black Sea Region coast is limited to a few narrow valleys because mountain ridges, with elevations of 1,525 to 1,800 meters in the west and 3,000 to 4,000 meters in the east in Kaçkar Mountains, form an almost unbroken wall separating the coast from the interior. The higher slopes facing northwest tend to be densely forested. Because of these natural conditions, the Black Sea coast historically has been isolated from Anatolia. The mild, damp oceanic climate of the Black Sea coast makes commercial farming profitable. Running from Zonguldak in the west to Rize in the east, the narrow coastal strip widens at several