'Black hole': What makes Russia's newest submarine unique? (Nov 2016)• Russia Beyond
The Russian defense industry has completed the construction of a diesel-electric submarine of Project 636.3, the Kolpino, for the Black Sea Fleet.
The submarine, dubbed by NATO naval experts as the "Black Hole" for its stealth and underwater capabilities, is equipped with the newest Kalibr-PL cruise missiles with an effective range of up to 2,500 kilometers (1,550 miles).
The submarine will be based at a new Russian naval base in the city of Novorossiysk in the Krasnodar Territory, 760 miles south of Moscow. However, until a dock for it has been completed, the new submarine will be carrying out service duty in the Black Sea and will undergo maintenance at the port of Sevastopol.