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

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

Hear the quietest sound from across the dome.

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

The only "Egyptian" pyramid in Europe and the legendary tomb of Remus.

Now famous as the "Harry Potter bridge," this impressive concrete viaduct has long been an icon in its own right.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

Northern Ireland's Brobdingnagian stepping stones.

This medieval castle overlooking the Elzbach river looks just like it did hundreds of years ago.

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

This fantastical waterfall is hidden in a cave located in a cracked cliff.

San Francisco's newly reopened hands-on science museum.

New York City's smallest piece of private property.

One part local history, 99 parts gruesome haunted house.

One of only two commuter aerial tramways in the United States.

Scores of vintage street lamps shine along L.A.’s Miracle Mile.

Florida might be at its most surreal in this museum devoted to the famed Spanish artist.

The most visited, and possibly most controversial, museum in Germany.

Ride the subways of yesteryear.

The most iconic structure in Scotland has been home to bishops, colonels, and Sean Connery characters.

Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

Relics of the 1894 Midwinter Exposition continue to delight visitors today.

Medicinal spa created with the discharge from a geothermal energy plant.

Elevated freight railway turned wildly successful urban park.