The smallest of the Trójmiasto (Tri-Cities), the Baltic Sea spa town of Sopot is smack between Gdansk and Gdynia, just a few miles from each. A retreat for the rich and royal for centuries, Sopot’s exclusive air remained even through the Communist era, and the tony town has undergone a building boom in recent years. Boasting beautiful beaches and ritzy resorts, Sopot is also known for its Wooden Pier (the longest in Europe), the lovely mid-woods Forest Opera and lively Monte Cassino Street.