A 2000-year-old Roman amphitheater lies just below Guildhall Yard.

A 1,215-foot tunnel transports pedestrians beneath the River Thames.

Rebuilt remains of a temple to Roman god Mithras.

A student driver's nightmare.

Kings Cross Station pays tribute to its role in Britain's best-selling book series.

A 300-year-old tea shop that brought tea to the English people, not to mention the Queen herself.

One of the few remaining casualties of the London Blitz, this destroyed church has become an enchanting public garden.

This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the Harry Potter films.

One part local history, 99 parts gruesome haunted house.

Bronze sculpture celebrating the relationship between Churchill and Roosevelt.

Claiming to be the oldest hat store in the world, this historic haberdashery had a hand (and a head) in the creation of the Bowler.

The signs of a long buried road can still be found hidden beneath a London sewer grate.

Overlooked amid the tourist bustle of Florence, this museum is dedicated to the craft of stone inlay.

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

This sword isn't waiting for a king to pull it out. It was placed there by a saint.

"In the Dark" Restaurant in Paris offers dinner in complete darkness.

Hidden in an Italian forest is a completely homemade amusement park that has taken a lifetime to create.

This Tuscan lake hides a 13th century town that is still visible when the water recedes.

A 16th-century horror show built in a lovely Italian garden.

This 16th-century monastery has been turned into a surrealist architecture compound.

These medieval skyscrapers dominate the skyline of this small Tuscan town.

Renaissance villa and gardens complete with a tormented colossus.

This domed temple was built in a hidden cave mouth as a refuge for sinners seeking absolution.

This natural gas vent certainly earns its name as the smallest volcano in Italy.