The unexpectedly beloved remnants of a controversial thermal power plant.

An eclectic collection of thousands of items owned by the sculptor Frederic Marès.

The oldest giants in Catalonia are now displayed in a 14th-century Gothic church.

A former steam-powered mill from the 1800s is now an industrial park with a giant steel dragon slide.

Barcelona's historic 19th-century sewers, whose foundations were laid in medieval times, are open to the public for exploring.

This Sri Lankan cemetery is the final resting place of sci-fi legend Sir Arthur C. Clarke.

An ancient stone fortress considered by many to be the eighth wonder of the world.

Huge herds of Asian elephants can be seen walking, bathing, and just chilling at this Sri Lankan park.

The small peaceful island off the Venice tourist circuit is where the city began more than 1,500 years ago.

As can be expected from a centuries old church built in a canal city, the undercroft of this house of worship is beautifully flooded.

An incredible menagerie of more than 3 million taxidermied animals at the oldest science museum in Europe.

One of the most important yet well-hidden museums dedicated to the history of medicine.

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

A magnificent Neogothic tomb hides within this Italian fairytale-like forest.

A 16th-century horror show built in a lovely Italian garden.

Water and windows define this defensive Italian well.

Romans built the world's tallest artificial waterfall in 271 BC.

This picturesque Umbrian city has a subterranean side that has long remained hidden.

Walk through living pictures and music in the Cathedral of Images.

London's creepiest cemetery was once the site of dueling magicians and mobs of stake-carrying vampire hunters.

At Monet's beloved home you can still see the Japanese bridge, waterlilies, and weeping willows that were the subjects of some of his most iconic paintings.

France's most famous cemetery, with some of its most curious tombs.

The vast, legendary catacombs hold secrets much stranger than stacked bones.