Thousand-year-old trees tower within one of the world's only inland temperate rainforests.

Running under an entire mountain, the longest highway tunnel in North America is kept fresh using portal fans and jet fans.

This small city where almost everyone lives in the same building can only be reached via North America's longest tunnel.

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

A group of college students hauled a desk up a mountain more than 40 years ago. The notebooks inside have become a makeshift time capsule.

European castle ruins in an American state park are actually the product of death and grief.

A monument to the King's final show, complete with a time capsule.

A free park where visitors can learn about and collect 440 million-year-old fossils.

An unusual, super-sized grocery adventure awaits in an Ohio suburb.

Rare recess caves fill this unbelievably beautiful Ohio park.

The largest earthwork effigy in the world.

Where beautiful signs live on forever.

A 30-foot stack of piano keys memorializes one of the greatest keys players in jazz history.

A battle between nature and architecture in the Cambodian jungle.

A modern mechanical planetary system, part of a 10,000 year clock.

This library and museum is dedicated to the life and literature of the Indianapolis native author.

The largest collection of historical roller skates in the world.

Home to the world's largest quilt collection dating from the 1600s through today.

An ode to "The Queen of Appalachia."

Rural churches in the middle of nowhere with religious frescoes by famous artist.

The world's longest outdoor covered escalator system transports commuters through Hong Kong's hilly terrain.

This naval gun is fired every day at noon, an odd timekeeping tradition the origin of which is local legend.

Remnants of the most densely packed city in world history, that thrived on anarchy for 30 years.

Teeming with illegal goods and services, this towering maze of vice is also a popular tourist accommodation.