K-535 Yuriy Dolgorukiy is the first Borei-class ballistic missile submarine of the Project 955 in service with the Russian Navy. Named after the founder of Moscow, Yuri Dolgoruki, the vessel was laid down on 2 November 1996 and was first planned to enter service in 2001. However, the R-39M missile that the Borei class was supposed to carry was abandoned after several failed tests, and the submarine was redesigned for the Bulava missile. The Bulava missile is smaller than the original R-39M, and in the 2007 START treaty data exchange it was reported that all Borei-class submarines would carry 16 missiles instead of 12, as originally intended. As of January 2013 the submarine is active with the Russian Navy. Borei II would carry 20 Bulava Missiles, first submarine would be active early 2018.