The stately remains of Llywelyn the Great's mighty fortress.

At high tide this strange footbridge appears to have no purpose whatsoever.

A hermit's tiny cell built into the cliffside that saved him in South Pembrokeshire.

Islanders once used this dramatic, otherworldly landscape to hide their cattle from Viking raiders.

Now famous as the "Harry Potter bridge," this impressive concrete viaduct has long been an icon in its own right.

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

This crumbling folly looks like an enchanted left over from Middle Earth.

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

This haunting stone chasm is a hotbed of mossy rock and English legend.

The last inhabitants of one of the U.K.'s most remote islands were evacuated in 1930.

Largest lake in Great Britain measured by surface area.

An ancient Scottish rock formation said to be the gravesite of a giant remains ensconced in legend and intrigue.

This stately estate house features a tower covered in a bright, modern mural.

One of the oldest and certainly best preserved Cistercian abbeys still in existence.

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

The true age of this ancient stone circle is unknown, but its stunning vista isn't in question.

A rocky sea serpent hides caves, blowholes, and a spectacular natural bridge.

The highest peak in the United Kingdom has a history of physics, specters, and a pilgrimage of strange objects.

A subterranean playground in an abandoned slate mine.

The one-time stronghold of the noble Douglas family, now home to ghost sightings and nesting birds.

The ruins of this gorgeous clifftop castle look like something from a fantasy novel.

Ancient cliffs resembling a kilt on Scotland's second largest island emit an entrancing sound.

The largest greenhouse in the world is home to over one million types of plants.

The gloomy ruins that inspired Bram Stoker to bring Dracula to life.