You'll want to browse the collections at Erarta Museum and Galleries of Contemporary Art, C-189 Submarine Museum, and Pushkin Flat-Museum. Some landmarks that you won't want to miss include Menshikov Palace, Strelka, and English Embankment. You can watch performances at Mariinsky Theatre, Alexandrinsky Theatre, and Oktyabrskiy Big Concert Hall if you're interested in local theater.