People of the Plum Bayou culture built these enormous mounds over 1,000 years ago.

Sid Vicious famously punched a hole in the wall of this iconic music venue.

An adorably sweet display of sculpted Precious Moments figurines.

This mill has survived a tumultuous past to still produce flour and cornmeal.

An outsider art studio that created a piece of work so popular they had to turn mainstream.

A hillbilly theme park that proved so unpopular the land wouldn't even sell on eBay after it closed.

Two gushing waterfalls of hot spring water within a block of each other.

The largest self-built castle in the U.S., six decades in the making.

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

Paranormal experiences in this hotel's room 217 led Stephen King to write "The Shining."

A small store filled with animal skulls and other curiosities.

A downtown park built on top of unclaimed graves.

The huge collection of paintings of the American West is one of Denver's best-kept secrets.

This museum offers an actual time machine back through Colorado's past.

Overlooking the Colorado Convention Center is this giant sculpture made from thousands of triangles.

A beautiful combination of living flora with preserved bones covers the shelves of this shop.

A multiversal transit station located right below a highway interchange.

At this Denver landmark, the meals are compulsory, the sopapillas are complimentary, and the insanity is everywhere.

This open-air reconstruction of an Old West town, a cross between a theme park and a museum, provides an immersive historical experience.

Each year, teams of the world's best snow sculptors have 65 hours to create frozen masterpieces.

A church of bones, decorated with 40,000 human skeletons.

This museum inside Amsterdam's largest cemetery explores how people deal with death.

This massive mural by famed pop-artist Keith Haring was hidden for almost 30 years until its 2018 rediscovery.

Three connected pink triangles memorialize persecuted gays and lesbians throughout history.