Natural catch-basin rocks covered in thousands of drawings spanning many millennia.

The house's confection-like decorations are the result of one man's painstaking work over decades.

This mountain tram provides stunning views while hanging from a single, steel thread.

A modernist landscape of water and sci-fi concrete.

The world's second largest single-dish radio telescope, once used to contact E.T.

This former railroad bridge was named after the great river that once flowed below it.

The abandoned remains of this once-thriving hotel looms over the city, awaiting an uncertain future.

A magnificent waterfall nestled in the heart of the El Yunque National Forest.

Legend tells how a Spanish soldier disappeared from this isolated sentry box without a trace.

This tiny home was originally a narrow alleyway.

This bleach-white graveyard overlooking the ocean is accessed through a tunnel.

Years of neglect and nature took a toll on this 19th-century lighthouse.

An enchanting natural wonder in Puerto Rico's Camuy River Park.

This former sugarcane transport tunnel is now a portal to a lovely beach.

This chapel on a cliff is renowned for its healing powers and was founded on the site of a supposed divine intervention.

The bat-covered home of one of the world's most popular brands of rum is located on a tropical Art Deco campus.

This niche museum devoted to ancient religious artifacts is shaped like the very thing it displays.

A haunted hill that supposedly defied gravity.

Four glass boxes hover over 1,000 feet in the air to give visitors an unparalleled view of Chicago.

The oldest cemetery in New Orleans, resting peacefully for over 200 years now.

A 200-year-old bar in the historic French Quarter refuses to give up its place in history, nor its role in securing ours.

A collection of oddities including Dr. Kevorkian's suicide device, the Thanatron.

The only swimming pool listed on the National Register of Historic Places is emptied and refilled each day with naturally filtered water.

The final resting place of New Orleans' most famous voodoo priestess.