The mansion home of author Edith Wharton.

The railroad tunnel nicknamed the "Bloody Pit" for taking the lives of hundreds during its construction.

Oldest existing church in New York and the inspiration for Washington Irving's "The Legend of Sleepy Hollow."

The home of one of America's most wealthy industrialists is now a historic site that remembers a more decadent time in the country's history.

With statues of Nelson Mandela and Harvey Milk this monument has been called the Mount Rushmore of California.

Dive bar built out of the remains of a whaling ship.

The memorial to the victims of the Jonestown Massacre carries the names of 918 lost, including one name people wish wasn't there.

The world's largest outdoor organ is played weekly by one of just two civic organists in the U.S.

A working model of the entire San Francisco Bay and much of the Sacramento River Delta, complete with regular tides that change every 14 minutes.

William Smith's iconic "map that changed the world" is hidden behind a curtain in the Geological Society building.

Commercial airplanes land mere feet over the heads of sunbathing beachgoers on this tiny island.

A modernist landscape of water and sci-fi concrete.

Of course the grave of JFK's assassin is surrounded by conspiracy theories.

In memory of the 110 victims of ValuJet Flight 592 that crashed in the Everglades.

The burial place of 14 of the executed leaders of the Easter Rising.

Experience what life was like in Ireland during the Viking and medieval ages.

A devastating booze inferno poured through the streets, claiming several victims who drank it.

A mysterious plaque to the even more mysterious "Fr. Pat Noise," killed in "suspicious circumstances."

The enchanting archway is the only surviving portal into Dublin’s lost medieval wall.

This neon landmark has been posing this deadpan question to follicly-challenged Dubliners for over 50 years.

An 80-year-old plane tree is devouring an iron bench at Ireland's oldest law school.

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

Dublin's "Dead Zoo" serves as a window to Victorian museum design.

Catholics make up 84% of Ireland's population but this Dublin museum remembers the small but important Jewish community.