Positioned on an island in Lake Mälaren, 11km (6 3/4 miles) from Stockholm, this is the most famous 18th-century theater in the world. It stages operas and ballets with performers done up in full 18th-century regalia, from period costumes to wigs, and the 18th-century music is performed on antique instruments. Its machinery and 30 or more complete theater sets are intact and in use. The theater, a short walk from the royal residence, seats only 450, which makes it difficult to get tickets. The season is from May to September. Most performances begin at 7:30pm and last 2 1/2 to 4 hours. You can order tickets in advance by phone with an American Express card. Even if you're not able to get tickets for an actual performance, you can tour the theater as part of a visit to Drottningholm Palace.