The Kara Sea is a marginal sea, separated from the Barents Sea to the west by the Kara Strait and Novaya Zemlya, and from the Laptev Sea to the east by the Severnaya Zemlya archipelago. Ultimately the Kara, Barents and Laptev Seas are all extensions of the Arctic Ocean north of Siberia. It is named after the Kara River (flowing into Baydaratskaya Bay), which is now relatively insignificant but which played an important role in the Russian conquest of northern Siberia. The Kara River name is derived from a Nenets word meaning "hummocked ice".
The Kara Sea's northern limit is marked geographically by a line running from Cape Kohlsaat in Graham Bell Island, Franz Josef Land, to Cape Molotov (Arctic Cape), the northernmost point of Komsomolets Island in Severnaya Zemlya.
The Kara Sea is roughly 1,450 km (900 mi) long and 970 km (600 mi) wide with an area of around 880,000 km2 (339,770 sq mi) and a mean depth of 110 metres (360 ft).
Its main ports are Novy Port and Dikson and it is important as a fishing ground although the sea is ice-bound for all but two months of the year. Significant discoveries of petroleum and natural gas, the East-Prinovozemelsky field, an extension of the West Siberian Oil Basin, have been made but have not yet been developed. In 2014, US government sanctions resulted in Exxon having until September 26 to discontinue its operations in the Kara Sea.