Twice a day a speeding train passes only inches from the homes of this residential neighborhood.

World's largest cave was only discovered in 1991, and now offers tours to the public.

This network of tunnels housed an entire village for years, and even had a hall for screening movies.

Vietnam's feral abandoned water park offers access to a post-apocalyptic funscape, now with fewer crocodiles.

An extravagant monument to an extravagantly unpopular Emperor.

This Vietnamese hell cave lets visitors take a walk through a devilish underworld full of demons.

This bridge is embedded with a giant steel dragon that breathes fire from its mouth.

This spectacular bridge supported by two gigantic hands looks like something out of a fantasy universe.

Vietnam's largest Buddha statue depicts a female sage.

What was once an underground Nazi city is now Europe's largest bat reserve.

Norway has built what may be the world's most beautiful public toilet.

Legend says lovers who hold hands while venturing along this stone jetty and kiss at the end will remain together forever.

The only remaining U-boat that is still floating never actually saw any action in World War II.

The northernmost point in Denmark is a turbulent sandbar created by two clashing seas.

Climb atop one of the world's longest and heaviest trains for an unbelievable journey across the Sahara Desert.

An illuminated manuscript comprising the life's work of a lone monk, inexplicably decorated with a portrait of Satan himself.

A favorite with sightseers, this Norwegian funicular provides easy access to a stunning view of Bergen and its environs.

If there is one thing you don't want to be in Sweden during Christmas, it's a Yule Goat.

An ornate Thai pavilion in the middle of Sweden.

Said to be one of Sweden's most haunted places, this vicarage once even attracted a ghost-busting priest.

Winter roadtrips are a little more exciting on this seasonal, slippery expansion of Sweden's national highway system.

The first overseas server for Facebook in Sweden's tundra.

This lake-bound geographical marker sits at the point where three European countries intersect.

From under the bed of one of the co-founders, this server helped launch the notorious file-sharing website.