You might want to spend some time browsing the exhibits at Erarta Museum and Galleries of Contemporary Art, Military History Museum of Artillery, or C-189 Submarine Museum. Strelka, Russian Admiralty, and Peter and Paul Fortress are monuments to see when you're exploring the area around Tuchkov Bridge. You can catch a show at Mariinsky Theatre, Alexandrinsky Theatre, and Oktyabrskiy Big Concert Hall.