The oldest family-run luncheonette in New York, last renovated in 1948, still serves food and drinks the old-fashioned way.

A treasure trove of artifacts, books, and artwork from the "golden age" of exploration.

A ruined mansion hidden in the woods of the Hudson Valley, home of a tragically doomed romance.

Vacant Beaux-Arts buildings that serve as reminders of a beach town’s glory days.

Exquisite wall sculptures carved in secret by an early quarryman in an obscure corner of the Paris Catacombs.

This statue was given to France by the United States to commemorate the centennial of the French Revolution.

France's most famous cemetery, with some of its most curious tombs.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

This eye-popping Icelandic crater lake is surrounded by red volcanic rock.

An encyclopedic collection of mammal penises.

This collection of grinning ephemera has grown from basement to Brooklyn.

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.

This whimsical group of statues is a favorite of children who love to climb all over Lewis Carroll's beloved characters.

The "Seinfeld" diner.

The former estate of the Guggenheims, part of the opulent Gold Coast that inspired the Great Gatsby.

Decades after testing the polio vaccine on unwitting patients, this historic mental hospital sits in ruin.

See some of the world's greatest racing horses at this idyllic thoroughbred breeding facility and garden complex.

This ancient Irish tower could easily have stood in for Rapunzel's prison.

An Irish church where an 800-year-old mummy is reaching out of his coffin as if to shake hands.

Mysterious 500-year-old tapestries depict a unicorn hunt.

The ancient tomb acts as a calendar that keeps perfect time.

An homage to everyone's favorite prehistoric cartoon family.

A semi-scholarly approach to sex.

The only structure left with direct ties to the Salem witchcraft trials of 1692.