Tropical paradise strewn with hundreds of World War II wrecks.

The ruins of an ancient island city built atop a coral reef in the South Pacific are spectacular and strange enough to have inspired H.P. Lovecraft.

A remote coral island with a gristly history of shipwreck, battles, and a horrendous war crime.

An isolated dive site teeming with cnidarians.

Giant money stones of Yap.

This Big Sur waterfall drops 80 feet directly into the Pacific Ocean, and inspired the hillside house up top.

A painted-over wall in Detroit originally built to segregate a black community from an adjacent white development.

This elaborate towering structure was once famed for its revolutionary height.

One of the indelible moments of the American Revolution took place at this location.

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

This quirky hot springs town known to locals as "T or C" was named after a radio show.

This whimsical group of statues is a favorite of children who love to climb all over Lewis Carroll's beloved characters.

The entire length of the border is marked by a 20-foot-wide slash through the trees.

Yo, Adrian!

The site of the climactic scene from the classic horror film is now a historic landmark.

Haunting and beautiful trees, doomed to die.

The actual model from the original "Star Trek" series is now on display at the National Air and Space Museum.

A giant open-air sculpture made of over 200 full-sized boats.

Decades before the scandal, this staircase on the river was a literal "water gate."

The second building of its name to occupy this location might be the finest flatiron building in San Francisco.

An ancient Roman theatre restored to its former glory in the Spanish city of Cartegena.

This whimsical seashell-shaped place of worship was designed to blend into its surroundings.

This isn't your average roadway—it's actually a National Park and a transportation pioneer.

This fort down the Potomac from Washington, D.C. was once the only defensive fort protecting the capital.