B-585 Sankt Peterburg is the lead boat of the Lada-class submarines of the Russian Navy. The Lada class is the fourth generation of diesel-electric submarines designed and constructed in the former Soviet Union and Russia to replace the Kilo class. Construction of the boat started in December 1997, and she was launched in October 2004. After undergoing a series of sea trials, Sankt Peterburg was commissioned in May 2010. However, the Russian Navy decided not to accept the St. Petersburg class after it was discovered that the boat's propulsion and sonar systems were inadequate. After design corrections the submarine was accepted. In 2014, Sankt Peterburg joined the Northern Fleet. In 2023, it was reported that due to the extremely high costs of modernising the submarine, the Sankt Peterburg was to be decommissioned and scrapped, with the funds being diverted to new submarine construction.

Lada class, Russian designation Project 677 Lada is the new advanced class of diesel-electric attack submarine designed by the Russian Rubin Design Bureau. A program to develop a "fourth generation" diesel-electric submarine, it aimed to produce a highly improved version of the Project 636 with better acoustic signature, new combat systems and possibly air-independent propulsion. However, in 2019, Alexander Buzakov, the head of the Admiralty Shipyard, indicated that there were no plans to equip the Lada class with an air-independent propulsion system. In July 2022 it was reported that work on an electrochemical generator to produce hydrogen from diesel fuel and oxygen was continuing and that the Rubin Central Design Bureau signed a new contract in 2019 to continue work. This was scheduled to be completed by the mid-2020s. In 2023, the decision was taken to decommission and scrap the lead ship of the class, the Sankt Peterburg due to the very high costs of modernising the submarine.