You'll want to browse the collections at New Tretyakov Gallery - Museum of Modern Art, Gallery of 19th and 20th Century European and American Art, and Pushkin Museum of Fine Arts. Cathedral of Christ the Savior, Armoury Chamber, and Grand Kremlin Palace are notable landmarks to explore if you're in the area. You can watch performances at The Cherry Orchard Theater, Moscow Arts Theatre, and Maly Theatre if you're interested in local theater.