Caspian Sea and a Pleistocene stage, that includes glaciation cycles and the creation of the present Volga River. During the first stage, the Tethys Sea had evolved into the Sarmatian Lake, that was created from the modern Black Sea and south Caspian, when the collision of the Arabian peninsula with Western Asia pushed up the Kopet Dag and Caucasus Mountains, setting definitive south and west boundaries to the Caspian basin. This orogeneic movement was continuous throughout the years, while Caspian was regularly disconnecting from the Black Sea. In the late Pontian, a mountain arch rose across the south basin and divided it
Caspian Sea the Caspian via a number of portages that connected the Volga and its tributaries with the Don River (which flows into the Sea of Azov) and various rivers that flow into the Baltic Sea. Primitive canals connecting the Volga Basin with the Baltic have been constructed as early as the early 18th century. Since then, a number of canal projects have been completed. The two modern canal systems that connect the Volga Basin, and hence the Caspian Sea, with the ocean are the Volga–Baltic Waterway and the Volga–Don Canal. The proposed Pechora–Kama Canal was a project that was widely discussed