Thanks to its architectural gems and world-renowned art collections, St. Petersburg is the crown jewel of Baltic cruising. Fortunately, many Baltic cruises spend at least one night in port so travelers can maximize their time. One of the more memorable aspects of a Baltic Cruise is the period surrounding the summer solstice, when St. Petersburg celebrates endless hours of sunlight with a multitude of festivals and concerts. Other highlights of a Baltic cruise may include Riga, Tallinn, Gdansk, Warnemunde, Copenhagen, Stockholm, Helsinki and Oslo. Baltic cruises primarily operate between May and September.