This picturesque lighthouse at the edge of the Irish Sea looks like a giant stone pencil.

Local legend says there's treasure hidden within its crowded graveyard.

A former watering trough turned local heritage site.

A Victorian marvel of engineering is now a 21st-century tourist attraction.

A medieval abbey featured on 'Game of Thrones' that dates back to the 12th century.

The last Victorian market in Belfast.

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

The "Black Arch" guards the entrance to the picturesque Glens of Antrim.

A peace symbol in Northern Ireland is among the world's largest hedge mazes.

The ruins of this medieval castle in Northern Ireland have inspired artists from C.S. Lewis to Led Zeppelin.

A meandering boardwalk across the bogland leads to a "stairway to heaven" with sublime views.

The atmospheric road was never meant to be so creepy.

This tiny train shuttles passengers to one of Northern Ireland's most spectacular sights.

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

This short bridge is the only thing connecting a tiny Irish island to the mainland.

Northern Ireland's Brobdingnagian stepping stones.

Scotland's only funicular railway is also the United Kingdom's highest.

Built in the 16th century, the tower is now in ruins.

A small, former industrial site overlooking Loch Kinardochy.

Did the legendary Scottish knight William Wallace actually take refuge here after a major battle?

This 16th-century tower house has a little hidden secret and a connection to an Apollo astronaut.

Nine hundred years ago, this was the home of a feudal lord. Today all that remains is a steep mound surrounded by a deep moat.

The ruins of a 12th-century seaside castle on the southwest coast of Scotland.

Now in ruins, this abbey was the home of Tironensian monks for more than 400 years.