While there's plenty to so in Charlotte Amalie on land, it would be a great loss not to explore the underwater wonders of the U.S. Virgin Islands. The easiest thing to do is rent a snorkel and explore the shallow waters by the beach, but you should definitely consider trying something more advanced at least once. Snorkelling is the cheapest choice. Add some diving equipment to go deeper and see more. Some tours now offer Sea Trek helmets — a modern take on the diving helmet. No matter your choice of equipment, do explore the coral reefs that are home to tropical fish such as snapper, hamlets, parrot fish, sturgeon, squirrel fish and majestic sea turtles.

The Rheinturm (built 1979 – 1982, architect H. Deilmann) is a striking landmark on the Düsseldorf’s Rhine skyline. It stands on the edge of the southern city centre, at the entrance to the MedienHafen, right beside the North Rhine-Westphalian parliament building (Landtag) and the building of the public broadcaster, Westdeutscher Rundfunk. It is 240.5 metres high, with a glass-fronted 180-seat restaurant at an altitude of 172.5 metres that rotates on its axis. A bar and lounge is located below the restaurant (168m) as is a viewing platform (164m) with a breathtaking view of the Rhine metropolis: the MedienHafen, the Altstadt, the Hofgarten, Königsallee and the Rhine with its family of bridges all lie at the feet of the tower. When the weather is good, one can see as far as Cologne Cathedral. Thanks to a level entrance in the basement of the tower, the building offers barrier-free access.

Containing over 23 million items, in the form of books, CDs, DVDs and many more, The Boston Public Library is an impressive building containing impressive collections. Take a tour or peruse the holdings of the nation's first public library, which also displays the works of famous artists and sculptors.