A collection of huge Pre-Colombian structures in Alabama.

The last intact steam engine factory in the United States.

This ancient settlement contains some of the largest earthen mounds in North America.

A dramatically eroding canyon thousands of miles from the desert.

A four-hour holy-rolling, Hallelujah-shouting, Southern gospel service, rendered as a country market where "All Is Welcome, Jews, and Gentiles."

A blues musician so talented that people said he must have traded his soul to the devil was born in this house.

Built by prisoners of war, the largest small-scale model ever built includes eight miles of tiny streams that now sit abandoned.

This iron and wood Civil War city-ship was the first vessel to be sunk by an electrically detonated torpedo.

For 150 years one family has been producing the iconic hot sauce on a bayou island made of salt.

This Louisiana folk art gallery is a gnarled collection of driftwood homonculi.

The first plantation museum in the United States to focus on the lives of enslaved people.

World's largest precision optical instrument used to detect Einstein's elusive gravity waves.

A once crucial portion of the Long Island railroad still lays abandoned, waiting to be turned into an urban park.

340 bicycles, 65 feet high.

Hand-powered race of alternative forms of transportation.

This collection of hand fans doubles as a history of femininity.

A huge work of Burning Man-inspired outsider art on the grounds of a California winery.

A trash dump made beautiful by nature's power.

Celebrating the transformation of trash into objects of beauty.

The mysterious round rocks of Schooner Gulch.

A library built during San Francisco's pioneer times is a student's retreat, bibliophile's sanctuary, and chess player's delight.

Russian history in San Francisco.

A shining, cold, black organ lies in San Francisco's financial district.

An invitation-only museum of items natural and bizarre, arcane and exotic.