This massive stained-glass masterpiece is thought to be the largest Tiffany dome in existence.

Quaint, disturbing, and macabre objects are all on display at this intriguing collection of medical instruments from bygone eras.

Near Birmingham, England three and a half miles of top-secret tunnels housed a World War II “shadow factory” and a Cold War nuclear bunker.

This 15th century pub is one of only two pubs in England situated on consecrated ground.

The highest peak in Wales is said to be the final resting place of a giant killed by King Arthur.

This ancient abbey now lies in majestic ruin behind a caravan park.

This charming railway is one of the oldest and steepest funiculars in England.

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

A spiral staircase connects the limestone cave with Pembroke Castle, birthplace of King Henry VII.

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

The mysterious, fantastical woodland inspiration for "The Lord of the Rings."

Centuries of human activity have forged an eerie landscape of ruins and craters on an exposed and windswept hilltop.

A harem-inspired Moorish fantasy design in a Victorian-era Welsh castle.

This Roman amphitheater is said to be King Arthur's legendary Round Table.

Neolithic burial chambers hidden beside a village school.

High Victorian fantasy created a fairytale castle out of a ruined fortress in Wales.

Rare collection of medieval books under lock and key.

The largest known medieval map of the world.

A 13th-century fortified manor house that was once sieged during the English Civil War.

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

An amazing collection of curiosities hidden in a small Welsh village.

This 500-year-old Tudor home is a treasure trove of history and mystery.

The Stonehenge of Wales is one of the grandest neolithic dolmens still in existence.

Beasts and branches swirl in sandstone carvings, interrupted by one strange creature.