The world-famous Hermitage art museum, which houses one of the biggest and best art collections in the world, and the two most beautiful summer palaces, built by mighty Peter the Great and Catherine the Great to rival Versailles will amaze the most tempted traveler. Nevsky Prospect, Mariinsky theatre, Saint Isaac's Cathedral, the great fortress of St Peter and St Paul, Peterhof, and the Church of the Spilt Blood are all not to be missed.