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

This unreal Portuguese palace looks as though it's made from a pile of different castles.

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

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

Remains of the artificial harbours invented for the Allied invasion of Normandy can still be seen at sea.

A castle-like sea fort from the 17th century is now a museum to oyster farming.

This black church sits alone among a field of lava rock.

Iceland's largest lagoon is home to stunning multi-colored icebergs.

This tumultuous Icelandic lava field looks so alien European researchers want to use it as a stand-in for Mars.

This wrecked airplane has been sitting on a black sand beach since the 1970s.

Twisted girders are all that remain of an Icelandic bridge that was wiped out by a combination of volcanic heat and glacial floods.

This eye-popping Icelandic crater lake is surrounded by red volcanic rock.

Largest private bird collection in Iceland, formed from a tragic accident.

This elegant arc of a waterfall marks a religious turning point.

Iceland: home to volcanoes, waterfalls and, apparently, Santa?

A trio of hidden hot tubs takes advantage of Iceland's natural geothermal vents.

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

Rising from the sea like a stone monster.

Staves, storm-calling, and of course, necropants.

Under a glass sidewalk lie the remains of some of Manhattan's oldest buildings.

The highest dunes in California are the most likely place in the area to hear the Singing Sands.

A charming desert roadside bakery that produces 10 times more bread daily than it has residents in its town.

This naturally heated mountainous creek has created a group of neon blue pools of potentially deadly boiling water.

One of the most unusual geological features, recognizable from a dozen hit movies.