You might want to spend some time browsing the exhibits at Grand Maket Russia Interactive Museum, C-189 Submarine Museum, or Erarta Museum and Galleries of Contemporary Art. St. Nicholas' Naval Cathedral, Saint Petersburg Conservatory, and Yusupov Palace are landmarks that you won't want to miss. You can watch performances at Mariinsky Theatre, Rimsky-Korsakov Conservatory, and Alexandrinsky Theatre if you're interested in local theater.