Walk behind a 50-meter-high waterfall.

A stunning silver lining to global warming's gloomy cloud.

This fantastical icy castle is built anew every winter.

Rubbing the buttons along this statue's coat is considered good luck.

Walk along the medieval fortifications that have been protecting Tallinn since the 14th century.

Burlesque Hospital Themed Restaurant.

This celebration of Latvia’s freedom and independence avoided demolition over half a century of Soviet occupation.

Twelve grave-faced marble angels guard the emperor's tomb at Les Invalides.

The water-powered carriages are long gone, but for over a century this funicular railway has been the fastest route to the highest point in Paris.

Known as the "Dodo Manège," this carousel features a herd of animals that have disappeared—or may be gone soon.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

This biographical museum honors the groundbreaking scientist at her birthplace in Warsaw.

This half-forgotten fortress was constructed by the Ottoman conqueror of Constantinople.

Large miniature theme park with 100-plus models.

Climb a steep hill in 90 seconds on the second-oldest urban subway in the world.

This museum was invented in a novel before being made real by the author.

A gorgeous, Gaudí-esque stairway constructed in the city of Istanbul by a prominent Jewish family.

Legend says if you stick your thumb in the hole and it gets wet, your wish will be granted.

A marvel of Byzantine engineering under the streets of Istanbul.

Ancient ruins hidden underneath a modern luxury hotel.

This is the oldest Roman-made bridge in the city still existing in its original state.

This ancient market is often referred to as the oldest shopping mall in the world.

The spot where the fascist dictator made some of his most famous speeches including declaring war on Britain and France.

Inside this McDonald's you can dine on your Big Mac and fries next to a 2,500-year-old Roman wall.