A mysterious chasm in the heart of the ancient Roman Forum, the Lacus Curtius was once believed to be a gateway to hell.

This Roman arch marks the location of an ancient gate at one of the Seven Hills of Rome.

One of several skulls claiming to belong to the beheaded St. John the Baptist is on display at this Roman church.

2300-year-old Roman road connecting the empire.

The yawning maw of this pagan visage is said to bite off the hands of liars.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

This New Orleans tree is filled with hidden chimes that produce a carefully tuned melody.

An old-timey wax exhibition campily depicting New Orleans legends and scandals.

This historic New Orleans cemetery is the final resting place of members of the Independent Order of Odd Fellows.

The tallest monument in a historic New Orleans cemetery was prompted by romance and dash of pettiness.

Parts of the civil rights movement unfolded in this historic eatery, helmed by the "Queen of Creole Cuisine."

An otherworldly musical haven in The Big Easy.

The only home of the famous French impressionist painter open to the public is now a museum and bed and breakfast.

The wreckage of a World War II bomber is hidden high in the Colorado wilderness.

A little-known subterranean street runs under some of the best-known buildings in Chicago's River North.

The iconic Chicago sculpture hides a beautiful and easily overlooked plaque on the backside.

These aggressively sustainable art homes look like something out of 1970's science fiction.

This Wyoming town is fascinated by a particular mythical creature.

Colorado's only true geyser is hidden within the San Juan National Forest.

An antique narrow gauge railway line still running through the Colorado and New Mexico mountains.

The childhood home of Henry Jones Jr. is now an adventure-themed bed and breakfast.

Gleaming self-built castle towers made from beer cans and inspired by "Vitamin Mary Jane."

One of few remaining antique carousels with stationary animals in the U.S.

The largest dinosaur trackway in North America is tucked away among this canyon's ghosts and archaeological gems.