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

Famously misunderstood wonder of the ancient world

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

The longest hedge maze in the world.

This once-controversial and slightly confusing statue of Achilles was built out of captured cannons.

Climb to the top of its spiral spire for spectacular views of Copenhagen.

The dance of this huge clock is a magnificent and eerie commentary on good and evil in the history of humankind.

This otherwise ordinary close on the Royal Mile constituted the end of the world for Edinburgh’s poorest residents.

The most loyal of little dogs, or a Victorian era publicity stunt?

Overlooked by many, the two famous Scottish warriors guard the main gate of Edinburgh Castle.

This alley off Edinburgh's Royal Mile contains remnants of the city's seedier history.

This single-track road rewards brave drivers with stunning Scottish scenery.

Northern Ireland's Brobdingnagian stepping stones.

A museum marks and documents the site of the Titanic's launch.

These engineering masterpieces are a dominant feature of the Belfast skyline.

The ship built to ferry passengers and goods to the doomed Titanic is now the last remaining White Star Line vessel.

A giant sculpture of the legendary "Salmon of Knowledge" celebrates the return of fish to Belfast's River Lagan.

Belfast's namesake river still winds below the city center, hidden from sight.

It was once nicknamed "the most bombed hotel in Europe."

These barriers stand as stark reminders of Northern Ireland's troubled past.

At high tide, the base of the lighthouse covers practically every inch of the island.

World's largest working waterwheel has been around for over 150 years.

The plunge pool is a surviving relic of a rowdy royal residence.

A six-ton wedding present for the King of the Scots.