Hear the quietest sound from across the dome.

Several plaster noses are hidden in plain sight around London's Soho neighborhood.

Rebuilt remains of a temple to Roman god Mithras.

Eighty million natural history specimens call this gargantuan museum home.

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

A hands-off space for graffiti artists to hone and display their skills.

One part local history, 99 parts gruesome haunted house.

An unusual round church in London with a Templar past.

A student driver's nightmare.

A charming 17th-century alley is lined with secondhand bookstores and antiquarian shops.

This London pub hides a peculiar secret: a recreation of the rooms shared at 221b Baker Street by Sherlock Holmes and Dr. Watson.

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

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

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 first ‘Harry Potter’ film.

Dublin's most modern, visually spectacular bridge is modeled after Ireland's national emblem.

This memorial was created by an Irish nurse who lived in New York City during 9/11.

At the time of its construction, this hydroelectric power plant was the largest in the world.

This rare and ancient Christian relic is one of Ireland’s oldest freestanding stone crosses.

This cemetery overlooking the Benbulben rock formation is the final resting place of one of Ireland's most beloved poets.

An Irish peat mine has become a stunning sculpture park.

A retired military stronghold on the rolling green coast of Donegal.

This colorful and fiery mural depicts the Irish folk story of the beloved hero Cuchulain.

This modest plaza in Moneygall, Ireland has cashed in on its distant connection to the U.S. president.