The site of a concentration camp where inmates were made to take part in one of the largest counterfeiting operations in history is now hauntingly empty.

San Francisco's oldest surviving monument and meeting place for 1906 survivors.

The last remaining relic of San Francisco's glittering 1915 Panama Pacific Exposition.

Staircase winds down the side of Telegraph Hill through gardens, wild parrots flying overhead.

Monument to a forgotten NYC disaster that claimed the lives of 1,000.

A crumbling staircase in upper Manhattan is all that remains of one of the most important sites in sports history.

The site of the deadly Triangle Shirtwaist Factory Fire.

A posh members-only club with a literally dramatic history.

Manhattan's lighthouse, erected at the insistence of the unsinkable Molly Brown.

Hidden in an ordinary Midtown building is a one-room museum dedicated to the greatest escape artist.

The privately owned cemetery that holds room for Washington's finest when they step down from life.

The remains of the worst maritime disaster in the history of the "Graveyard of the Pacific."

Walk a trail through a historic Quaker town that outlawed slavery in 1777 and was a major waypoint on the Underground Railroad.

The Cambridge pub where Francis Crick announced that he and James Watson had discovered the DNA double-helix.

Small teepee-like houses built for TB patients have become sheds, studios, and bus stops around Colorado Springs.

This network of tunnels housed an entire village for years, and even had a hall for screening movies.

A Himalayan monastery claims to have a piece of a centuries-old abominable snowman.

The second oldest Jewish graveyard in the U.S. is tiny, with connections to George Washington and Henry Wadsworth Longfellow.

A distillery built on (and above!) mobster Dutch Schultz's Prohibition-era underground moonshine business.

A subterranean shelter remains intact under a busy Paris railway station.

Legend has it that President Grant’s frequent drinking in the lobby gave rise to the term “lobbyist.”

A popular day's outing in Bovington consists of watching military tank driving practice.

This historic home of the author of Lawrence of Arabia, has a history of literary celebrities and monogrammed sleeping bags.

This seemingly charming home memorializes and honors the victims of a century-old unsolved murder.