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

This imaginative sculpture is a memorial to this town's former mining industry.

400-year-old garden, restored to beauty.

A historic London pub with prison cells in the cellar and a "spy room" on the second floor.

A makeshift shrine to the late rock star is still kept up on the nondescript façade outside 1 Logan Place.

"Respectful to the dead, safe and sanitary to the living, dedicated to the Genius of Memory..."

Catacombs turned marketplace.

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

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

Famously misunderstood wonder of the ancient world

The world's largest collection of witchcraft regalia.

Hidden beneath the streets of London is a secret subway that only carried mail.

An easily overlooked stretch of ornate window fronts and gaslight lamps that could be right from the pages of Dickens.

This South London cemetery holds the remains of more than 15,000 people.

This dramatic landscape hidden on the Isle of Skye looks as though you've stepped into the magical realm.

The mysterious, fantastical woodland inspiration for "The Lord of the Rings."

The world's third-largest crystal sphere has sat in the Penn Museum since 1927 with the exception of one outlandish theft.

South Philadelphia is home to Keith Haring's only surviving in situ collaborative public mural.

An Irish Memorial commemorating those who perished due to potato blight.

The first American axe throwing club.

A tour de force of a fountain, memorializing a man who loved fountains more than anything else.

This Philly landmark has a giant butterfly pavilion, three floors of insect displays, and withstood a $40,000 heist.

A daily replay of the experiment that proved the rotation of the Earth.

The sounds of the world's largest fully functioning pipe organ dazzle shoppers at a Philadelphia Macy's.