The world is full of swimming holes, but few compare to Samoa’s idyllic To Sua ocean trench.

This castle-fortress is a living example of the transition from medieval defenses to modern fortifications.

The largest man-made crater in the U.S. marks the spot where we once tested mining with nukes.

This logic-defying 16th-century Tudor manor still stands to the delight and astonishment of onlookers.

Hide from the tourist hordes in these relatively unknown, and unguarded lava caves.

One man's dream has turned into this naturally growing chapel made of almost nothing but trees.

This wooden recreation of a 9th century lake village looks as though it was built yesterday (which it relatively was).

The highest monastery in the world operates a tiny guesthouse with doors open to all.

The last bastion of Roman presence north of the Alps looms over a German town.

This volcanic cave lake is essentially hard proof that Iceland is the most magical place on Earth.

In ancient times, these fallen standing stones supported a massive house.

This skewed English house has looked like it's going to fall over for centuries.

According to the local folklore, the myriad colors of this lake are the result of a lovelorn wizard's blunder.

This old-fashioned carhop restaurant gave the world the waffle cone.

The Guinness Record holder for largest hedge in the world is a verdant Scottish bulwark.

Take a steam-powered ride straight out of the past on this Appalachian rail line.

One of the most scenic falls in Massachusetts has a history of death and grim legend.

A strangely forgotten claimant to the much contested title of "Source of the Nile."

New England's tallest light house stands on an island with a history of cannibalism and death.

Despite time, colonization, and the brutal New Mexican heat, these Pueblo ruins still stand.

A top secret Cold War bunker hidden beneath a Latvian spa facility is now open for tours.

This 19th century cyclorama acts like an analogue time machine to a different era.

A former fisherman's hut deemed too small for habitation is now a delightful tourist draw.

This awesome Spanish castle is so fantastical it was actually used on Game of Thrones.