Ruined 11th century abbey built by King David I in Edinburgh, Scotland.

The mysterious image is believed to show Edward Hyde, 3rd Earl of Clarendon, in a beautiful blue dress.

The home of the first American-born saint is one of the only curved buildings in New York.

A museum collection honoring the long history of the FDNY is held in a disused Manhattan fire house.

Touching mementoes from those who didn't make it back from World War I still hang in one of New York's oldest bars.

A bit of retro transportation flair preserved in the world's largest department store.

The only home that Alexander Hamilton ever owned has a history almost as troubled as his own.

This cemetery has graves dating back to the 17th century, including the city's oldest carved tombstone and an ominous cryptogram.

This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.

Visit the monolithic tomb of America's most famous general.

An uber-secure, windowless tower of doom in the center of Manhattan is an NSA spyscraper.

The oldest house in Manhattan is now a museum that remembers the home's sordid history of scandals, vice-presidents, and ghosts.

Great place to have a drink and a bite to eat in an atmosphere laden with New York's Bohemian past.

The "Seinfeld" diner.

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

New York City's smallest piece of private property.

The ill-fated plan to reroute the Mississippi so that Union ships could bypass Confederate fortifications on the river bend.

The final resting place of the camel who served with the Confederate Army during the Civil War.

This iron and wood Civil War city-ship was the first vessel to be sunk by an electrically detonated torpedo.

A museum in Mississippi celebrates the history of Coca-Cola and the man who brought it to the masses.

The modern birthplace of Irish freedom.

The oldest public library in Ireland.

The gorgeous library at Trinity College is home to remarkable treasures of Irish identity.

One of Ireland's most infamous prisons for rebels including men, women and children.