A complicated contraption for telling time by the moon.

The excellent acoustics of this natural amphitheater made it a popular preaching spot for the founder of the Methodist Church.

This chain of artificial lakes was an ideal test ground for the aircraft that would carry the "bouncing bombs" used by the WWII "Dambusters" squad.

The world's longest covered bridge is a quaint and incredible wooden tunnel.

Nestled near the mountains of western Canada resides this behemoth earth mover.

Huge spherical rocks in the middle of the prairie.

The only way to visit this old resort hotel is with scuba gear.

The mountaintop wind turbine boasts a viewing deck — and a fair share of controversy.

Lake within a lake.

An unfortunate geological resemblance to Satan has labeled this Pasadena gorge as a passage to the underworld.

A Swedenborgian glass church surrounded by redwoods sits perched atop a massive landslide area.

Costumed elves and mountain bikers co-exist peacefully at this abandoned Christmas-themed adventure park.

Relics of the 1894 Midwinter Exposition continue to delight visitors today.

This weird abode has inspired everything from the "House On Haunted Hil" to a robot hunter's pad.

16,500-acre ranch filled with American heritage, geological wonders, and a giant pile of tires is the crown jewel of an intriguing tug-of-war.

The world's largest key collection features keys to the White House, Frankenstein's castle, and Hitler's bunker.

The world's largest carnivore sanctuary is home to over 450 meat-eating rescues.

An impressive collection of over 50,000 minerals including moon rock from the Apollo 17 mission.

A vast collection of rare books, manuscripts & extraordinary objects illustrating the history of medicine.

With some 500,000 books across five buildings, this bookstore is a reader's paradise.

The headquarters of the famous Yale society.

The beams of the New College, Oxford dining hall come with an amazing story.

The UK's oldest theme park slowly slips away.

This oddly named town refuses to change its phallic moniker.