Construction of Barcelona’s iconic (but controversial) church was finally completed in 2026—a century after the death of its architect.

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

A island reachable by a causeway at low tide is possibly one of the earliest Western European locations to be identified in text.

In Portugal, a secluded stretch of untouched natural beauty hides at the bottom of a steep hill.

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

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.

This narrow Ghent alleyway is an officially sanctioned street art tunnel.

The patron of this extravagant Art Nouveau confection insisted that nothing less than a boat should project from its facade.

A 14th-century fortified keep showcases the masterpieces of an ingenious 20th-century clockmaker.

This ghost town in Belgium will lose its street art when it ceases to exist.

Explore 400,000 years of humans' "battle against darkness" in this offbeat but thorough lamp museum.

This recently restored crypt was once plagued by liquefying coffins and exploding caskets.

A little sculpture with a large wardrobe.

Climb inside an iron crystal magnified 165 billion times its normal size.

An abandoned saucer-shaped monument in the Bulgarian mountains.

Once an opulent Art Nouveau hotspot, the Constanța Casino is one of Romania's most beautiful abandoned buildings.

This communist behemoth is the heaviest building in the world and a legacy of a brutal regime.

A marvel of technology a century ago, this disused power station now offers a lovely glimpse into the industrial design of the past.

The abandoned "Red Star Train Graveyard" is the final rusting place for precious artifacts of train history.