You might want to spend some time browsing the exhibits at New Tretyakov Gallery - Museum of Modern Art, Multimedia Art Museum, or Museum of the Moscow Railway. Shukhov Tower, Novodevichy Convent, and Tolstoy Estate are monuments to see when you're exploring the area around Gagarinsky. You can watch performances at Great Moscow Circus, Moscow State Variety Theater, and Moscow International House of Music if you're interested in local theater.