The largest crypt ever constructed in France was built in the 11th century on an ancient Druid sacred site.

It's possible to walk inside one of the largest Neolithic tombs in Britain.

Made famous by 'Star Wars,' these troglodyte homes face an uncertain future.

A preserved oasis with traditional Andalusian-style architecture and beautiful views of the Nile.

The largest cemetery in the American Southeast is a hidden gem near the heart of Atlanta.

This amazingly preserved Doric temple was abandoned before it was ever completed.

Exploring the wilder, more passionate sibling of Erg Chebbi feels like discovering a secret sun-kissed planet from another galaxy.

The world's first underwater farm is home to more than 700 plants.

A creepy, deserted mock Arabian village can be found in the middle of the Qatari desert.

Roughly 17 million letters to Santa have found their way to this Arctic Circle post office.

Whimsical sculptures dot a woodland path surrounding their creator's old summer cottage.

It is said that each of the white stones in the red facade of this medieval house represents the head of a murdered Swedish noble.

Stones speckled along Harris Avenue reveal hidden nuggets of the past.

Every Tuesday, students let off steam by screaming into the night air.

Grab a cuppa at England's first and only domestic tea plantation.

The secret wartime bunker built on the platforms of an abandoned Tube station.

The overgrown remains of an old rail bridge rise above the valley like ancient Greek ruins.

This stunning 15th-century royal hill fort preserves the age of chivalry in Rajasthan.

This abandoned bridge to nowhere stands secluded in the woods of a Cleveland suburb.

The oldest still-inhabited hill fort in India looks like a magnificent golden sandcastle.

This medieval castle was painted pink as part of a now-abandoned children's theme park.

The evocative ruins of a 1,000-year-old hill fort lie within a popular tiger reserve.

A giant red chair bolted to a rock on a remote mossy hillside in Iceland.

The land is full of geologic eye candy, such as otherworldly spires, mushroom-shaped hoodoos, and prehistoric fossils.