Ancient man-made caves underneath small town Belgium.

A magical and peaceful ruined Cistercian abbey in what is now southern Belgium.

The legacy of a Moroccan Jewish community is remembered at this little mouldering cemetery.

The true depths of these stunning Moroccan caves are unknown.

Rocky Atlantic beach home to a stunning stone arch.

One of the most spectacular canyons in the world.

An abandoned horror film set sits eerily along a highway through Hollywood's "door to the desert."

The final resting place to 300 Victorian-era pets hides inside the city park.

Small church on top of a huge rock column.

The 2,000-year-old Roman columns are hidden within Barcelona's Gothic Quarter.

The world's first hotel built in an abandoned water-filled quarry.

This Danish rock field is actually a sprawling ancient cemetery holding the bodies of 700 Vikings.

The ruins of an 11th-century Norman castle with a rare, perfectly circular shape.

This desert oddity hides in plain sight thanks to a cartographic error and a desert explorer with a punny sense of humor.

Strange rock formations tower above the river that snakes through this enchanting Icelandic canyon.

Two massive and unstable sinkholes are yearning to unite, and their consummation could be catastrophic.

A Victorian mansion, painstakingly reproduced to appear just as the the Munster's family home did on TV.

A popular swimming hole that hides one of America's most deadly diving spots.

A hospital where antique dolls are given new life.

The oldest (maybe) swimming pool in Iceland is a stunning oasis built into the side of a lush hill.

The summer tourists on these cliffs are thousands of seabirds.

A mysterious castle built as a monument to lost love.

A modern Nordic Pompeii on the Icelandic island of Heimaey.

This rusting remnant of the local herring industry is being given a second life.