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
Pontic–Caspian steppe shore of the Caspian Sea in the Dagestan region of Russia, but the drier Caspian lowland desert lies between the Pontic steppe and the northwestern and northern shores of the Caspian. The Kazakh Steppe bounds the Pontic steppe on the southeast. The Ponto-Caspian seas are the remains of the Turgai Sea, an extension of the Paratethys which extended south and east of the Urals and covering much of today's West Siberian Plain in the Mesozoic and Cenozoic. Pontic–Caspian steppe The Pontic–Caspian steppe, Pontic steppe or Ukrainian steppe is the vast steppeland stretching from the northern shores of the Black Sea