Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

Pilgrimage site for star-crossed lovers.

100 year tradition of fist fights, marked by marble footsteps.

The complex has been abandoned since the Croatian War of Independence, barring a stint as a set for 'Game of Thrones.'

A curious cave church carved into the face of a cliff.

A tiny church on a man-made island in the Adriatic.

This castle was established by the 4th Duke of Montrose and is connected to the Buchanan Clan.

Largest lake in Great Britain measured by surface area.

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

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

This little Greek plateau is home to thousands of rustic, white-sailed windmills.

Where commuters walk through remnants of an ancient Greek necropolis.

A Bronze age settlement on the Greek island of Santorini might have been the inspiration for Plato's Atlantis.

Swarms of dainty flying insects swarm into the Petaloudes Valley to get busy.

This imposing tower named after the mythical sword of King Arthur is considered the tallest freestanding climbing wall in the world.

The tallest waterfall in the Netherlands is a lovely, stepped feature that is only 50 feet tall.

This disused VLF radio station is no longer in service but the surrounding town still bears its name.

Go inside a revolutionary, cage-less zoo where 70 species of monkeys roam free alongside their human visitors.

This former steel and coal plant is now a neon-lit industrial fantasia.

The largest free-standing aquarium in the world resides in a hotel lobby in Berlin.