A labyrinthine network of chambers with a storied past hides below Edinburgh's South Bridge.

Some 46,000 years ago, a volcanic eruption led to a flooding event that carved this short canyon with steep vertical walls.

A roaring, awe-inspiring double cascade of icy water flows through woodland Oregon like something out of a Tolkien novel.

The highest point in Washington state is a volcano covered in glaciers.

See the imprints of ancient trees, burned and preserved by lava.

The longest continuous lava tube in the continental U.S. offers 2.5 miles of dark explorations for the adventurous.

The mayor made the declaration in 2004.

Every weekend, people gather here for a brief chance to see their loved ones on the other side of the United States–Mexico border.

Get three sheets to the wind at this desert winery with a nautical theme.

Considered by many to be one of the most dangerous highways in Alaska.

An important Mayan religious and trading center dating back to 200 BC.

A massive underwater sinkhole made famous by Jacques Cousteau.

Road signs in Namibia mark the location of one of the five major circles of latitude.

This "dead marsh" sits among the largest sand dunes in the world, a forest frozen in time.

The Dalai Lama named this New Zealand landscape the "Spiritual Center of the Universe."

Home to 23 voluptuous and instantly lovable sculptures by one of Latin America's most celebrated artists.

Outdoor escalators and art have helped change what was once a notoriously dangerous part of Medellín.

The world's tallest palm trees look like the whimsical kind of plant you'd find in a Dr. Seuss story.

An unusual and beautiful form of mass transit serves the city's steepest neighborhoods.

Striking, enormous gold-plated sculpture of Buddha installed in the 19th century.

Bangkok celebrated its shifting monarchy with a militaristic homage to democracy.

This dazzling Buddhist temple was constructed from over one million ceramic tiles salvaged from a British shipwreck.

In the world's most bombed country relative to its size, this incredible organization helps pick up the pieces.

When the USA donated cement and funds to expand the airport in Laos, the Laotians built a massive monument instead.