This war hero's old shop remembers the fine line between medicine and quackery during the Revolutionary War.

From buck blood to Theriak miracle tonic, this collection of Renaissance chemist's gear look's like a wizard's pantry.

The oldest operating pharmacy in the world features 800-year-old recipes.

A stunning 18th century pharmacy and medieval chemist's collection.

The only museum about the history of dentistry in Canada.

Ukraine's oldest operating pharmacy now offers guests a fascinating walk through apothecary history.

This museum looks at the history of one of America's most famous prisons and most beloved albums.

This former boomtown "island" is now submerged below Folsom Lake.

Folky pharmaceuticals abound in this medicinal reliquary.

300 years of pharmaceutical history on display.

Where the writer penned his famous story about a jumping frog.

A popular tourist cave with a dark past.

An old-timey medicine shop that once served Chinese laborers during the Gold Rush is still open for business to this day.

This Roman quarry once held secret masses and smuggler's contraband and is now home to rare species of bats.

Its dark depths conceal millions of rare, delicate crystal formations.

The beloved statue at the National Academy of Sciences is oh so inviting to sit on.

The beautiful tunnel that ran from the lobby to Penn Station is still hidden underneath 34th Street.

The construction of a tram line unveiled hidden remnants of the old medieval city.

A cavernous three-story, 43,800-square-foot basement that was forgotten about for 60 years.

A labyrinth of ancient tunnels hidden below the city holds the ruins of 2,500 years of history.

Hidden in a grotto 26 feet below Nottingham's oldest hotel, this stylish subterranean drinking den is notoriously hard to find.

This picturesque Umbrian city has a subterranean side that has long remained hidden.

Water and windows define this defensive Italian well.

This quaint Italian town keeps losing ground as the sides of its plateau slowly erode.