Two geoglyphs that are truly unique to North America.

A Norwegian-born sculptor created these soaring guardian angels at the entrance to Hoover Dam.

Brightly colored 30-foot-tall totems light up the desert sky just outside Las Vegas.

The neon signs from Las Vegas' past find their final resting place at this unusual graveyard.

Graffiti, cars, and religion combine to create this jungle of scrap in the Nevada desert.

These craggy limestone outcrops offer a glimpse at a unique piece of Florida geology.

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

This colorful gate stands as an entrance to the walled city of Old San Juan.

Invading U.S. troops were first seen from this now-abandoned tower, leading to the Spanish-American War.

Legend has it this historic port was a popular hideout and smuggling spot for pirates.

La Cara del Indio honors the Taíno chief who fought bravely against the Spanish invasion of Puerto Rico.

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

This former factory has been transformed into a technicolor wonderland, where dozens of local artists have collaborated to create a real choose-your-own-adventure experience.

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

Stunning ruins of what was once the center of one of the greatest empires in East Africa.

A salty red wasteland in Tanzania is a breeding spot for endangered flamingos.

In memory of the 110 victims of ValuJet Flight 592 that crashed in the Everglades.

A sculpture of 18 beautiful clay mandalas on display at Warm Mineral Springs in Florida sends a message of world peace.

This concrete sculpture features a woman opening her heart to showcase a beautiful fern.

St Bernard de Clairvaux Episcopal Church, better known as one of the oldest European buildings in the Western Hemisphere.

An alchemist's "magic door" stands in the middle of a Roman park.

A mysterious castle built as a monument to lost love.

This statue inspired by Renoir's famous painting embodies the jovial spirit of Key West.

An octet of classic chrome trailers speared into the ground act as a tribute to the silver bullets of the open road.