You'll want to browse the collections at B-413 Submarine Museum, Museum of the World Ocean, and Bunker Museum. Ruins of Koenigsberg castle, Brandenburg Gate, and Amber Museum are monuments to see when you're exploring the area around Park of Sculpture. You can watch performances at Kaliningrad Regional Musical Theatre, Kaliningrad Regional Philharmonic Hall, and Kaliningrad Regional Youth Theater for Young Spectators if you're interested in local theater.