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

Abandoned for decades, trains still pass through the now-restored remains of one of Madrid's first metro stations.

A lush indoor jungle fills this bustling Madrid transportation hub.

An ancient Egyptian temple in the middle of Madrid, Spain.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

Ruins of a German castle on top of a towering stone pillar.

This abandoned, partly demolished building is now home to beautiful graffiti and murals.

This former farm In northern Iceland is now a museum, where visitors can tour beautifully-preserved turf houses.

Dozens of large, brightly-colored paintings adorn the walls of the "street art capital of Iceland."

Europe’s most powerful hot spring supplies the surrounding region with hot water.

On an island south of Iceland, a large volcanic rock formation resembles an elephant.

A popular Icelandic children's story comes to life inside this cave.

This canyon is comprised of gorgeous waters and magnificent basalt columns.

A bit of the Berlin Wall was gifted to the Icelandic capital to commemorate the 25th anniversary of German reunification.

A modern Nordic Pompeii on the Icelandic island of Heimaey.

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

A formerly glacier-tipped volcano that inspired none other than Jules Verne.

This mountain fissure hides a secret path to a secluded mossy grotto within the rock itself.

This tiny museum's sizable collection is jammed into a former underground public toilet.

This hobbit-y little hot spring may be the oldest spring used by humans in all of Iceland.

The unique waterfall in Iceland's south features a backdrop of geometric black lava columns.

A giant concrete orb in far north Iceland marks the ever-shifting boundary.

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

The oldest church in Iceland is one of the few to feature ornate decoration.