You might want to spend some time browsing the exhibits at C-189 Submarine Museum, Erarta Museum and Galleries of Contemporary Art, or Alexander Pushkin Museum and Memorial Apartment. Yusupov Palace, Mariinsky Palace, and St. Isaac's Cathedral are notable landmarks to explore if you're in the area. You can check out the local talent at Mariinsky Theatre, Mariinsky Theater Concert Hall, and Mikhailovsky Theatre.