Slaughterhouse Five opens its dank doors to fans of Kurt Vonnegut.

Follow the original medieval paths that wind through this intriguing section of the city.

The remains of a remote village that once housed over 1,200 dam workers and their families.

A winding medieval path was used by mourners to carry their dead to the nearest church.

A dramatic sculpture high up in Yorkshire with vistas on an industrial scale.

A miniature train-ride through Slovenia's largest cave system.

This one-time health resort was used by aristocrats around the world.

Castle and secret tunnel withstood a siege until its owner was killed by the Holy Roman Empire, while sitting on the toilet.

The railway carts travelers to central Athens's highest peak, which offers stunning vistas of the city.

A marvel of Byzantine engineering under the streets of Istanbul.

Housing the famous Norwegian ice-defying 19th century polar exploration ship.

Across the Pacific in a raft, a museum dedicated to Thor Heyerdahl's now legendary expedition.

Home to three historic ships from the age of Vikings.

The true age of this ancient stone circle is unknown, but its stunning vista isn't in question.

Summer in Scotland begins with a spectacularly wild and colorful event rooted in ancient pagan traditions.

Ruined 11th century abbey built by King David I in Edinburgh, Scotland.

Gargantuan home of Russian science.

An iconic Soviet statue of working-class people.

World's largest bell sits on the grounds of the Kremlin in Moscow.

Moscow's imposing monument to the Space Age.

Former headquarters of the KGB.

A sculpture park of the tossed aside relics of the USSR, from Stalin to a massive Soviet emblem.

Museum celebrating the achievements of the Soviet space program.

The gorgeous entrances into the city's underbelly look more like grand halls than subway stops.