A memorial to Wellington's well-loved, well-traveled wharf dog.

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

The bridge is a secret gallery of discarded gum that has been transformed into miniature masterpieces.

London's last remaining public soapbox site has seen speeches from Karl Marx, Vladmir Lenin, and George Orwell.

Legend says these colorful, invasive residents are the descendants of birds released by Jimi Hendrix.

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

Eighty million natural history specimens call this gargantuan museum home.

This ancient oak plays host to carvings of magical elves, gnomes, witches, and other creatures prominent in local folklore.

This pub was 238 years old when it decided to revamp its image: It started serving Thai food.

This unique bridge curls up like a caterpillar to let boats pass and then unfurls again to span a small canal.

After nearly 60 years, there's still a bear at Paddington Station looking for help.

This iconic high-rise residential block was one of the last to be built in the Brutalist style.

The deepest underground city in Turkey was designed to protect 20,000 people behind massive stone doors.

These tombs were built into the side of a mountain so that ancient angels could reach the dead.

Roman ruins, natural methane fires and a lovely beach.

The bunker where Hitler took his own life is hidden under this deliberately ordinary parking lot.

On the Spree bank, discover one of the last reminders of a symbolic wall that divided, and was torn down by the people.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

The most visited, and possibly most controversial, museum in Germany.

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

A semi-scholarly approach to sex.

Elevated freight railway turned wildly successful urban park.

Climb a steep hill in 90 seconds on the second-oldest urban subway in the world.

This remarkably well-preserved Egyptian plinth is pretty well traveled for a giant piece of stone.