According to legend, this cavern holds the passage that Persephone used to travel to and from the underworld.

Hideout of thieves, monks, and goat-footed gods.

This beehive tomb built for royalty sat hidden for over 3,000 years.

The heads and relics of 179 monks slaughtered by pirates are on display within this Ceonobic Monastery.

The oldest standing Byzantine church in Athens is tucked within a monastery in the middle of an upscale shopping district.

A Byzantine-era church hidden in a wooded area below the Acropolis.

According to legend, this ancient column contains healing properties.

The ruins of this ancient fortification wall sit in the middle of a quiet, residential intersection.

After a catastrophic forest fire, a Greek artist transformed scorched tree trunks outside an old sanatorium into this haunting sculpture garden.

These caves secretly held national treasures during World War II.

An often overlooked ancient site in downtown Athens with substantial history (and nature).

A grotesque collection of wax limbs depicting the symptoms of venereal disease.

A Viking-style brewpub named for a Norse sea giant, in the heart of fjord country.

Thousands of birds nest in the cliffs while arctic foxes prowl below.

Ruins of two abandoned stations destroyed by the power they sought to harness.

The world's northernmost brewery uses water from a 2,000-year-old glacier to create its beer.

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

This abandoned mining village was predicted to resist decay longer than any other modern human settlement.

In the northernmost city in the world, it's illegal to be buried because it’s too cold for bodies to decompose.

According to the locals, the sands of this secluded Norway beach are infused with gemstone particles.

Cold storage for agricultural biodiversity.

Monuments don't get much more metal than these three giant viking swords planted in a Nordic hill.

Milan's duomo is covered in beautiful carving including a curious "dinosaur-like" beast.

A small island in Lake Garda that was used as a burial site, pirate hideout, and a monastery.