No one knows who's responsible for decorating this tunnel with stuffed animals, but the people love it enough to protest their removal.

Underground monastery and fortress.

These Stalin-era industrial 'death traps' hang lifeless above the city

Small church on top of a huge rock column.

One of the great treasures of Neolithic art lies within this carefully constructed pile of rocks.

An isolated 17th-century chapel on a remarkable site once dedicated to Celtic sun worship.

A granite rock formation littered with various species of moss, lichen, and fern.

This stone quarry was used to make axes and other tools more than 6,000 years ago.

If they push on just the right spot, even the weakest person can move this titanic boulder.

This extinct volcano rises above Edinburgh and is special for its panoramic views over the city.

17th century streets hidden under Edinburgh were once a breeding ground for the black death.

An artist's whimsical transformation of everyday objects.

A miniature of a lighthouse acts as a beacon for what transpires inside this location.

The ruins of this gorgeous clifftop castle look like something from a fantasy novel.

People leave coins atop an unusual grave marker in one of Scotland's oldest burial grounds.

This Industrial Age architectural and engineering gem helps visitors and residents alike traverse Lisbon, “The City of Seven Hills.”

A king's pet, a pope's gift, an artist's inspiration, and a tragic shipwreck.

One of the largest Roman settlements in Portugal.

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

Perhaps the most spectacular grotto along the Algarve coastline.

Considered the birthplace of the Copper Age and Bronze Age, the river is tinted red from 5,000 years of mining.

This artificial cave looks like something out of a fairytale.

An abandoned textile factory on the "island of crows" was home to Estonia's first workers' strike.

A program of Communist glamour in post-Stalin Poland is preserved in this colorful museum.