Severomorsk, known as Vayenga until 18 April 1951, is a closed town in Murmansk Oblast, Russia. Severomorsk is the main administrative base of the Russian Northern Fleet. The town is situated on the coast of the Barents Sea along the Kola Bay 25 kilometers northeast of Murmansk, the administrative centre of the oblast, to which it is connected by railway and a motorway. It is the main naval base of the Northern Fleet of Russia and the sixth largest city in the world beyond the Arctic Circle.