It is the oldest remaining stairway William Penn created to give Philadelphia citizens access to the port area.

This mechanical marvel is a 24-hour cheese vending machine, holding freshly made cheeses from the internationally acclaimed Perrystead Dairy.

Yorktown’s grandest colonial home still wears the scars of the siege that helped end the American Revolution.

As the oldest natural history museum in the Americas, these halls contain everything from dinosaur bones to biological samples collected by Lewis and Clark.

Iceland's largest geothermal mud pool is a little bit haunted and a little bit dangerous.

Eerie ruins of an abandoned medieval fishing village crumble atop an unforgiving stretch of earth.

Cairns built to bring travelers good luck stretch across the land like miniature stone mountains.

This verdant, tree-lined Reykjavik graveyard is both enchanting and eerie.

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

A relatively obscure antihero from the Marvel Comics universe adorns a wall inside Iceland's main airport.

The remains of a hospital that housed over 200 leprosy patients.

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

Medicinal spa created from the mineral-rich runoff of a geothermal power plant

Walk in the footsteps of the gods and straddle two tectonic plates.

An unusual building on a "desolate hill" features the works of an Icelandic sculptor.

This plaque tells the story of an event that took place in an imagined parallel universe.

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

A geothermal paradise with bubbling mud pools and bright blue hot springs.

This natural Icelandic fissure allows divers to swim right between two volatile tectonic plates.

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

Surrounded by ash fields in Iceland, an impossibly verdant valley looks like something out of a fairytale.

Strange rock formations tower above the river that snakes through this enchanting Icelandic canyon.

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

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