A traveling postal dog covered 48 states and more than 140,000 miles, and he lives on as taxidermy, patched up with a rabbit's foot and a pig's ear.

This quirky UFO-shaped curiosity is often mistaken for the airport’s control tower.

This historic address is home to the beloved ball and is an almost totally empty building among the most expensive real estate in the world.

The watery entrance for condemned prisoners heading to the Tower of London is still visible along the Thames.

Lady Liberty's first beacon of enlightenment is now displayed in a museum near the statue.

Charles Babbage's proto-computer, painstakingly brought to life.

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

This sculpture by artist Fritz Keonig survived the 9/11 attacks and now stands as a monument to the victims.

The unluckiest U-boat in the entire German fleet is now on display in a Chicago museum.

Amidst the bustling streets of Dublin, there is a hushed garden that is dedicated to "All those who gave their lives in the cause of Irish Freedom."

The somber sculptures commemorating Irish Famine on the river Liffey in Dublin.

Scattered throughout London are ancient remnants of the city's former bounding wall.

Twelve grave-faced marble angels guard the emperor's tomb at Les Invalides.

The modern birthplace of Irish freedom.

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

The oldest public library in Ireland.

A nun spent 16 years painting the stunning Celtic mural that covers the interior of this WWI memorial.

The mummified heart of a saint lives on in this church—after a brief hiatus when it was stolen.

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

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

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

The only "Egyptian" pyramid in Europe and the legendary tomb of Remus.

The popularity of Sherlock Holmes led to the creation of his fictional address, turning the orderly London street numbers askew.

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