This striking observation tower shaped like a spinnaker sail is the newest icon in historic Portsmouth.

The Last Home of an Executed King.

Famously misunderstood wonder of the ancient world

A giant white horse drawn on an English hillside may not have been intended to be a horse at all.

The first archaeological site discovered by aerial photography.

Europe's largest prehistoric mound – burial site of a legendary king?

The largest stone circle in the world has ended up bringing up more questions than it has answered.

The rotting skeleton of a shoreside fun fair that was destroyed by fire and storms still haunts the Brighton ocean view.

At just 51 feet and 10 inches long, it's the shortest street in England.

A replica of the steam engine that hauled Queen Victoria's Royal Train is on display at Windsor.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

The birthplace of Karl Marx is now a museum dedicated to the communist revolutionary's life and work.

An expansive complex of subterranean tunnels is all that remains of one of Europe's most formidable medieval fortresses.

This temple to the sturm and drang of Richard Wagner contains a dragon's cave and reptile zoo full of living "dragons."

It is said that each of the white stones in the red facade of this medieval house represents the head of a murdered Swedish noble.

The largest oak in England is said to have been the hideout of Robin Hood and his Merry Men.

Semi-precious Blue John stones have been mined in this cavern system for centuries.

A magnificent winding road through a steep valley, with deep natural caverns at the bottom

Some of England's last cave dwellers lived and worked within this huge cave.

This chain of artificial lakes was an ideal test ground for the aircraft that would carry the "bouncing bombs" used by the WWII "Dambusters" squad.

6000-year-old site covered in more than 50 megaliths.

A gorge full of caverns where early humans lived alongside cave hyenas, giant mammoths and wooly rhinoceroses.

A German apartment building hosting as many trees as human occupants.

This monument to those fallen in the World Wars is accompanied by a U-boat that Germany bought for a Deutsche Mark.