This massive collection of British military artifacts includes the heartbreaking personal letters of the men in the trenches of WWI.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

One of Scotland's most important modern structures, it just made the '100 Most Endangered Sites' list.

A glacial pothole was once a hideout for a notorious Scottish outlaw.

The oldest library in Scotland was built from the remains of a church to hold a churchman's library.

This unusual rock looks like a giant, otherworldly mushroom sprouting atop a cave.

Scotland's first free lending library, which protects literacy through inheritance.

Monty Python fans will recognize this abandoned mine as the Cave of the Killer Rabbit of Caerbannog.

This Neolithic stone circle is the most complete of its kind in Scotland.

These skilfully executed, poignant works of art dot a verdant Scottish dell.

On a hill overlooking Loch Trool, a granite boulder marks the site where Robert the Bruce, King of Scotland, defeated an English army.

Believed to be the birthplace of John Balliol.

A 30-acre garden inspired by the principles of modern physics.

Stonehenge has nothing on Castlerigg’s views.

This beautifully situated lakeside Roman settlement was likely built during the reign of the Emperor Hadrian.

A 2,000-ton rock resting in a state of a delicate balance.

What was once England's second-richest abbey is now a haunting ruin.

One of the highest Roman forts in Britain is set amid dramatic scenery on a notoriously difficult road.

One of the best-preserved, yet least visited stone circle sites in Cumbria.

The rust covering this old mine's abandoned buildings matches the red pigment it once produced.

This temple was constructed entirely by Roman soldiers.

“It has nae lugs!”

Also known as "Robin Hood's tree," this tree became a famed location along Hadrian's Wall before it was cut down in an act of vandalism.

Built as a training camp, this site became a detainment center for prisoners of war and German civilians during World War I.