This obscure walkway links Edinburgh’s Old Town with one of the city's prime vantage points.

Accessible only at low tide, the deserted island is dotted with World War II ruins.

There are plenty of wonderful panoramic vistas in Edinburgh, but not many are hidden smack in the middle of the Old Town.

One of the oldest scientific gardens in Britain, containing more than 13,302 plant species in its core collection.

17th century streets hidden under Edinburgh were once a breeding ground for the black death.

A metal tree emits eerie, melodic notes on top of Lancashire's Crown Point.

One of these two land speed record-breaking vehicles went so fast it shattered the sound barrier.

This ruined medieval castle was the scene of Lord Robert Dudley’s seductive reception for Queen Elizabeth I.

The longest canal aqueduct in England was built without a plan to get water past the moving boats.

A decommissioned tube carriage within a London museum hosts a regular pop-up supper club.

The majority of the museum's large collection is held in a storage space open to the public a few times a year.

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

Hear the quietest sound from across the dome.

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

A kaleidoscopic warehouse-maze of handmade neon signs.

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

This Maryland farm is known for its amazing corn mazes and its 30-foot junkbots.

These unassuming lighthouses have seen the first reading of the Pledge of Allegiance, the first wireless transmission, and more than one mystery.

An outlandish shoe shaped house built by an eccentric millionaire.

This shale formation along the Appalachian Trail once inspired the third president of the United States.

Built in the 1850s, this church was of the first five churches constructed in Harper's Ferry.

The whimsical twist of this spire was either caused by the Devil, an unexpected virgin, or lead.

The longest and tallest aqueduct in Britain can actually be sailed across.

One of Canada's most incredible rare book collections holds hundreds of thousands of gorgeous tomes that the general public can touch.