Bubbling up from deep underground is the warm crystal clear water that fills the Warm Springs Pools, America's oldest spa.

The oddly shaped, steam-spewing building is now an art studio and gallery.

America's first public mental health facility.

An alternate history park where the Union Army loses the war... to dinosaurs.

Paranormal investigators claim this abandoned asylum is the most haunted spot in the eastern U.S.

Exact replica of the ancient monument, but much, much lighter.

Outsider art meets paleontology at this roadside reptile repository.

A haunting tribute to pioneering photographer Clover Adams.

Rumor has it the uncarved lump behind the three famous suffragists is reserved for the first woman president.

Enormous piles of historically significant stones, dumped by Congress in a forest, and abandoned for 60 years.

The Byzantine, pre-Columbian, and medieval art at this stately mansion are some of the most under-appreciated collections in D.C.