This massive swimming pool is the high tech home to the human-powered submarine races.

A relic of FDR's brief foray into utopian urban planning.

The world's oldest continuously operating airport was founded by the Wright Brothers.

This scenic Maryland park was the site of one of the worst prison camps of the Civil War.

The land is home to swimming ponies and a legendary 18th-century treasure.

This beloved Baltimore spot features caged dolls, a giant Pez collection, and many, many mannequins.

The site where Poe “in great distress, and ... in need of immediate assistance” likely died.

Built in 1347, this belfry is one of the oldest in the world and survived intense bombing during World War I.

One of the oldest and largest wooden churches in France was very evidently constructed by shipbuilders.

A monument to the thousands of Canadian soldiers who died capturing the French ridge during World War I.

Today this former Nazi concentration camp stands as a poignant memorial to the victims of fascism, and a warning from history.

A fortress on this island housed the mysterious prisoner known as the "Man in the Iron Mask" for more than a decade.

This bunker in northern France was built by Nazi German forces with the intention of launching up to 50 V2 rockets at London each day.

An effigy of a trapped paratrooper dangles from a Normandy church to commemorate one remarkable D-Day event.

Site of one of World War I's most horrific scenes.

Remains of the artificial harbours invented for the Allied invasion of Normandy can still be seen at sea.

Underneath a chalk hill in France lies what Hitler hoped would be the underground launching base for a devastating new weapon.

The castle was reconstructed to fit Kaiser Wilhelm II's romanticized vision of the Middle Ages.

This ancient theater was once the home of fierce gladiatorial battles.

This ancient Roman bridge and aqueduct still stands as a wonder of classical construction.

The mental institution where Van Gogh created some of his most famous work now allows guests to walk in the artist's footsteps.

Hundreds of hidden passageways weave through the old quarters of Lyon.

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

The prototype for all Nazi concentration camps.