An extraordinary natural landscape of mountains, waterfalls, and rocky cliffs riddled with tunnels.

The handiwork of a underdog clockmaker who solved an impossible problem for an Empire, and forever revolutionized seafaring.

A 1,215-foot tunnel transports pedestrians beneath the River Thames.

Ruined 11th century abbey built by King David I in Edinburgh, Scotland.

The most loyal of little dogs, or a Victorian era publicity stunt?

The heads of two giant mythological water horses honor Scotland's horselord past.

Where a young athlete began his run across Canada after losing his right leg to cancer.

A quarter mile off the coastal tip of Maine you'll find the "Beloved Island" of Franklin Delano Roosevelt.

The world's largest rotating world.

This tiny patch of arid sand sits in one of the greenest states in the United States.

Once the future of underwater combat, this old sub is now open for visitors to muck around in.

Surprisingly aquamarine waters fill deep lakes formed at the end of the last ice age.

The largest source of fossilized insects anywhere.

Thanks to a quirk of elevation this gift shop produces magic doughnuts that are found nowhere else on Earth.

The superstar of Cold War nuclear bunkers has been featured in countless films but is now barely operational.

This grand stone tower was dedicated to a famed American humorist almost by coincidence.

Strange red rock formations that have been attributed to a higher power for hundreds of years.

These faux-cliff dwellings allow visitors to climb around on a replica archaeological site.

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

This Brazilian palace island was once the site of the last grand ball before revolution.

This massive Brazilian church is built like an angular, technicolor pyramid left by Mayans from the future.

A bright little alley in La Boca is a part of tango history.

Since the 1700s, this old barrel has acted as a post box that relies on the kindness of travelers.

An enormous and lavish Gothic church in Czechia.