This abandoned five-star hotel is now a five-star urban exploration destination.

An early work of the architect Álvaro Siza Vieira, these swimming pools blend into the beach.

The verdant mossy ruins of a Franciscan monastery lie in the remote Sintra hills awaiting exploration.

The medieval castle built as headquarters for the Pope's secretive Knights Templar.

An ancient and majestic fortress that played an integral role in Portugal's road to independence.

This gaping hole in the middle of a remote mountain lake looks like a portal to another dimension.

A submerged village appears when dam levels drop.

A 16th century chapel decorated with bones, skulls, and entire bodies hanging from the wall.

Located in the thermoelectric factory that once powered the entire city, this Portuguese museum is shockingly fascinating.

Ring the bell to enter a bar that looks equal parts museum and old curiosity shop.

This charming candle shop has been in business since 1789.

Japan's largest area of "pink moss" turns the hillside bright pink every spring.

A restaurant modeled after feudal Japan, where the waitstaff are trained as ninjas.

Every autumn, this hillside is ablaze with red summer cypress.

The magical, mossy forest that inspired Princess Mononoke.

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

A subterranean shelter remains intact under a busy Paris railway station.

Paris' linguistic guide to the international language of, yes, love.

Abandoned railway line circling the city of Paris.

The oldest stone house in Paris was built by its most famous alchemist.

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