The first skyscraper to include a Ferris wheel built into the facade.

The charmingly disheveled clock tower of Tbilisi's puppet theater.

Rock-hewn monastery complex with hundreds of cave structures tucked away into the mountainside.

Underground monastery and fortress.

This deceptively salty lake looks like blushing pink lemonade.

Despite a fraught and controversial history this African island holds a powerful monument to the tragedy of the slave trade.

New Zealand's only running funicular railway.

Largest Kauri tree in New Zealand.

This unusual rock formation looks like an apple that has been neatly sliced in half.

A galaxy of glowworms—larvae of a gnat—hides deep in the belly of these caves.

This strange geological landscape erupts with sudden bursts of water.

The glacier tucked within a New Zealand rainforest.

Dolphins, ancient clams and hundreds of waterfalls make this one of the world's top tourist destinations.

This sheep farm has been forever transformed since being built for “The Hobbit” film series.

Giant disc-shaped gate took 20 men to close off this city in Madagascar.

Fabulous formations, weird and wonderful wildlife.

This picturesque island graveyard is the final resting place of dozens of notorious pirates.

The centuries-old trees lining both sides of this dirt road may become Madagascar's first natural monument.

The "Little Ones," show Portugal in full miniature splendor.

A hidden three-foot-wide house separates these two regal churches.

Elaborate tile work in this railway station tells the story of Portugal.

A perfectly circular lake is formed by the crater of an ancient underwater volcano.

One of the largest Roman settlements in Portugal.

Elaborately carved to showcase the glorious wealth that the age of exploration brought to the Portuguese empire.