Saint Petersburg is the eighth map available in Mini Metro, being unlocked by delivering 500 passengers on Osaka. It is based around where Saint Petersburg, Russia is located. Delivering 500 passengers on Saint Petersburg unlocks Montréal, and the Подорожник achievement.
It is common for a Unique Station to spawn on one of the islands early in the game.
Delivering 1500 passengers on Saint Petersburg with tunnels on no more than one line unlocks the Neva the Great achievement.