A floating underwater hotel, created by a Swedish artist.

Remnants of an exploded schooner and wrecked submarines form a breakwater.

A statue of the second-tallest Dutchman in history.

An ultra-modern diversity park in Denmark has turned an entire city block electric pink.

This Stockholm light tower can be controlled by anyone with a smartphone.

This innocuous-seeming building is actually the remnant of a major wartime brothel.

This museum in a Paris apartment gives a unique look at the iconic French singer's life.

A popular shrine where the Blessed Virgin allegedly appeared in 1830, displaying a holy armchair and two incorruptible remains of Lady Saints.

A museum on the history of Paris, including a set of Napoleon's toiletries, Proust's room, and relics of the Revolution.

The very center of Paris is surrounded by a bevy of strange good luck rituals.

This massive library holds what was once the largest book collection in the world.

A giant interactive periodic table with real samples of the elements.

This walkway is so narrow it needs its own light to stop pedestrian traffic jams.

These brass bunnies honor the rabbits that dominated the no-man's-land around the Berlin Wall.

A fascinating insight into daily life in the Eastern Bloc.

A narrow passage next to a cafe leads to a courtyard exploding with murals, tags, and paste-ups.

The patron of this extravagant Art Nouveau confection insisted that nothing less than a boat should project from its facade.

The world's first cruise ship-shaped hotel is perched atop a cliff.

To enter the lower hall of this temple, you must first walk through a dragon.

One of the largest collections of socialist realist art shows the surprising depth of the official art of the Soviet Union.

A museum dedicated to controversial Russian pianist Alexander Scriabin.

A former special storage facility for documents during the Cold War.

Gargantuan home of Russian science.

The California secessionist movement has its own foreign embassy, in Russia of all places.