In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

The world's largest mountain carving could fit all of Mount Rushmore inside it many times over.

Construction of Barcelona’s iconic (but controversial) church was finally completed in 2026—a century after the death of its architect.

Wondrous sandstone hoodoos where Native Americans collected clay for pottery, 9,000 years ago.

Tiki luxury on Nob Hill.

An artsy hidden staircase leads to breathtaking views of San Francisco.

A huge musical instrument played by the ocean.

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.

The de facto symbol of Copenhagen is this bronze fairytale which cannot seem to keep its head for very long.

The yawning maw of this pagan visage is said to bite off the hands of liars.

An "anarchical" no man's land, complete with garbage sculptures and a hobo-run "Landfillian Library."

An ambitious developer built what was once the world's tallest fountain in a Phoenix suburb.

The massive, incredibly rare instrument is over 11 feet tall with a range so deep it goes lower than humans can hear.

Thousands of Mexican Free-Tailed Bats soar around an abandoned storm drain at sunset each summer.

A geological mystery on Camelback Mountain.

A historic hydroelectric power plant serves as the unusual backdrop for a public park.

This grinning pup statue is all that's left of what was once a ubiquitous Bay Area diner chain.

Forgotten and then destroyed by fire, this was once one of the largest saltwater swimming pools in the world.

Amazing meticulous gardens of personal wood carvings, Hydrangea, Canna, and many other flowers.

Sitting atop San Francisco's tallest hill, a cross honors the victims of the Armenian genocide.

A pair of slides and a tree-lined stair corridor have been an urban oasis for nearly 40 years.

This colorful boulder serves as a canvas for political statements and artistic expression.

Over a century old, this restored Victorian building is surrounded by a lush garden filled with rare palms.

Around the perimeter of San Francisco’s second-largest park is a meandering 2.7-mile path designed to inspire contemplation.