Ancient serpentine sacrifice holder that has stood the test of time.

Preserved Inca city and site of the last Inca stronghold against the Spanish conquistadors.

A geological mystery on Camelback Mountain.

A wild west cemetery in Tombstone, Arizona, provides a window into the Old West.

The ancient tomb acts as a calendar that keeps perfect time.

Air Force Academy Chapel made of 100 identical tetrahedrons works to inspire those of all religions.

A museum and shop on Bourbon Street located in the former home of the second Voodoo Queen of New Orleans.

An elaborate gift from Claus Spreckels is now a piece of San Francisco history.

Yo, Adrian!

Concrete strongholds stand guard over the Golden Gate.

Not merely a museum – but a whirring powerhouse that offers a subterranean peek into the heart and soul of cable car operations.

The unluckiest U-boat in the entire German fleet is now on display in a Chicago museum.

After starting as a whimsical tourist attraction that eventually found its way to ruin, these renovated canals offer a lush and exotic locale on the Pacific Coast.

A toxic ghost town sitting atop a massive coal fire.

Golden Gate Park's historic collection of plants.

This historic "City of the Dead" lies prominently in the center of New Orleans' famous Garden District.

Berthed at the Charlestown Navy Yard in Boston, "Old Ironsides" is the oldest commissioned warship still afloat.

A spiritual vortex among the red rocks in Sedona.

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

Dyed by iron oxide over centuries, these sandstone rocks rise thousands of feet into the sky.

A layered tribute to the work of mosaicist Isaiah Zagar.

Northern Ireland's Brobdingnagian stepping stones.

Paranormal experiences in this hotel's room 217 led Stephen King to write "The Shining."

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.