The Caspian Sea is bordered by five countries: Kazakhstan, Turkmenistan, Iran, Azerbaijan, and Russia. The sea is called “dead” because its high salinity prevents macroscopic aquatic organisms, such as fish and aquatic plants, from living in it, though minuscule quantities of bacteria and microbial fungi are present. In a nutshell, if the Caspian is considered to be a sea, then ownership of the seabed will be based on each country's coastline. If the Caspian is considered to be a lake, then the seabed will be divided evenly between all littoral states. The Caspian Sea is the largest lake on Earth by both area and volume, with a surface area of 371,000 square kilometres (143,244 mi²) and a volume of 78,200 cubic kilometres (18,761 mi³). It is a landlocked endorheic body of water and lies between Asia and Europe. It has a maximum depth of about 1025 meters (3,363 ft). The sea stretches nearly 1,200 km (750 mi) from north to south, with an average width of 320 km (200 mi). Its gross coverage is 386,400 km2 (149,200 sq mi) and the surface is about 27 m (89 ft) below sea level. Its main freshwater inflow, Europe's longest river, the Volga, enters at the shallow north end. Two deep basins form its central and southern zones. These lead to horizontal differences in temperature, salinity, and ecology. The seabed in the south reaches 1,023 m (3,356 ft) below sea level, which is the second-lowest natural non-oceanic depression on Earth after Lake Baikal (−1,180 m or −3,870 ft). Written accounts from the ancient inhabitants of its coast perceived the Caspian Sea as an ocean, probably because of its salinity and large size. With a surface area of 371,000 square kilometres (143,000 sq mi), the Caspian Sea is nearly five times as big as Lake Superior (82,000 square kilometres (32,000 sq mi)). The Caspian Sea is home to a wide range of species and is known for its caviar and oil industries. Pollution from the oil industry and dams on rivers draining into it have harmed its ecology. The Caspian Sea is salty, with about 1 percent salinity compared with the Dead Sea's 34 percent. Surface salinity impedes evaporation – a paper published in 2018 notes that the evaporation rate from the surface where freshwater enters the Dead Sea was as much as three times higher than from the salty surface. The Caspian Sea also shows varying levels of salinity. Overall, it is about one-third as salty as the ocean. The water is saltiest in the south and freshest in the north. Roughly 130 rivers feed the giant lake, and nearly all of them enter from the north or west. Can you swim in the Caspian? 3. Can you swim in the Caspian Sea? Most parts of the sea are perfect for swimming and relaxing. It has a fantastic climate, and not to forget that the sands in the Absheron peninsula, near Baku and other villages, are rich in minerals and salts with healing properties. Can you drink…