The largest catacomb system in the world.

Two towns are linked by an engineering marvel masquerading as a boring suspension bridge.

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

Bangkok celebrated its shifting monarchy with a militaristic homage to democracy.

A tall karst islet popularized by 007.

This hanging crocodile is thought to be the "dragon" that once plagued a Czech city.

This restored Portuguese cafe may well be the most beautiful place in the world to grab a Big Mac.

Mummified monks and the accidentally interred, in a 17th-century crypt.

The world's oldest bookshop still in operation.

This star-shaped military outpost is now simply trying to protect itself from neglect.

The medieval castle built as headquarters for the Pope's secretive Knights Templar.

Possibly the oldest church in Barcelona, this basilica has its pagan and Christian mythologies all mixed up.

World's strongest whirlpool.

The world's most charming instant portrait studio also happens to be its smallest.

The great polar explorer is remembered in this far northern town, where he embarked on his final expedition.

This functioning parish church is also the site of many concert performances due to its wonderful acoustics.

The world's northernmost aquarium looks like it has fallen over.

The convergence of two currents makes this a surprisingly pleasant getaway in the Arctic Circle.

This "preacher's pulpit" once used for pagan ritual, is home to a new, and dangerous ritual.

This grand hydraulic installation has provided water for townspeople since the Middle Ages.

Founded in 670, this ancient mosque is an architectural time portal.

The original film set of Luke Skywalker's Tatooine home from the 'Star Wars' trilogy.

This bridge was constructed from the rubble of the infamous Bastille.

The celebrated eyesore created by starry-eyed sweethearts.