Hiding the longest subterranean river known in the world.

The world's largest second-hand graces a clock surrounded by constantly changing flower beds. 

An opulent monument built for a duke who donated his entire fortune to the city of Geneva.

A beautiful ruin of a 14th-century Plantagenet castle built by a medieval mercenary.

This landmark overlooking Ramsbottom pays homage to Sir Robert Peel, repealer of the Corn Laws.

This well-preserved Cistercian Abbey in a romantic pastoral setting has inspired artists like the poet Wordsworth.

You can enjoy a (possibly haunted) stay at the medieval Norman castle that was once a favorite hunting lodge of King John.

One of the longest wooden benches in the world snakes around Geneva's Treille Promenade.

Home of the Large Hadron Collider and the birthplace of the World Wide Web.

A 14th century castle built on the seat of a mighty giant.

A 16th-century artillery fort built to protect England against European invasion.

A island reachable by a causeway at low tide is possibly one of the earliest Western European locations to be identified in text.

The luxurious English estate houses the world’s largest private collection of French Rothschild wines.

A seaside town with no sea in sight.

The world's largest grapevine has produced a delicious harvest at Hampton Court Palace for almost 250 years.

In 2013, historians discovered a hidden room devoted to the art of making royals' hot chocolate.

Carved initials which are nearly 500 years old preserve the deposed Queen's presence at Hampton Court Palace.

England's oldest surviving hedge maze has been confusing visitors for over 300 years.

Asthmatic Charles Hyett's son built a fantastical garden for his father to convalesce in, alas it was too late.

Locals call it the "Give Peas a Chance" bridge because of its distinct graffiti.

An ornate aviary built during the Victorian trend of collecting exotic birds.

Ivy-covered Medieval tunnels cut through this charming town in France's Loire Valley.

A massive base for the Nazis' most formidable weapon in the Atlantic.

The unusual stilted beacon is the town's only active lighthouse.