The only mine for rare earth elements in the United States has been intermittently active since the 1950s.

This Yellowstone geyser may not shoot as high as the nearby Old Faithful, but it erupts for considerably longer.

In Florida, these naughty monkeys live on their own mini-monkey Alcatraz.

Ruins of an old sugar mill sitting quietly next to a park in rural Florida.

A tribute to Ponce de Leon's supposed quest for eternal youth.

This shrine commemorates the site of the first known Catholic mass in the United States.

A luxurious 1880s hotel with its fair share of Tiffany stained glass, Edison electricity, and of course, ghosts.

An 18th-century Spanish watchtower made entirely of seashell and concrete.

This granite rock face is named for the magnificent reflection that occurs when the sun hits it just right.

Kentucky, Tennessee, and Virginia meet at this point in the Cumberland Gap.

Abandoned for 60 years, this submerged bridge was completely forgotten until the lake was drained.

The statue mysteriously lost its head and left hand.

The Acropolis house that became Modern Greece’s first university.

This church on a Tohono O'Odham reservation has stood since 1797.

Elevated freight railway turned wildly successful urban park.

A museum cafe showcases Native American dishes and indigenous ingredients from across the Western Hemisphere.

A hidden passageway now marks the site of an assassination attempt on Ronald Reagan that some say broke a 140-year-old curse.

With a history dating back to Victorian times, this architectural gem is a rare New York tourist haunt worth visiting.

Take a hike to this remote, scenic tea stop in the Canadian Rockies.

Five mythical trolls have taken up residence in woods and hidden on paths at the Coastal Maine Botanical Gardens.

An unusually designed bridge from the 1920s was built to withstand the tides and winds of Maine.

The California capital city once stood 10 feet lower than it does today.

I Street Bridge is the heaviest swinging center bridge in the United States.

This hiking/biking/horse trail along an old railroad grade features trestles, tunnels, and a roadless stretch through the scenic Susan River canyon.