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

This beach runway is off limits during high tide.

This volcanic plug boasts the longest recorded history of any Scottish stronghold.

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

The colorful stairs are made with marble from the world's major quarries.

The U.K.'s first underground railway line is now a lively thoroughfare for runners and cyclists.

Wonderfully preserved Victorian factory, complete with a preserved steam powered engine house.

A nuclear bunker built to shelter the politicians and important people of Scotland in case of nuclear attack.

This Shetland Islands bus shelter may be small, but it squeezes in a couch, a desk, some art, and even an old telly.

This abandoned oil depot produces world's longest echo in a manmade structure.

This Birnam-based garden honors the legacy of 19th-century children’s book author Beatrix Potter.

Anonymously sculpted and donated, these sculptures made from poetry books and pages are sprinkled around the city.

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

What happened to the three lighthouse keepers who vanished from this place remains a mystery over a century later.

Where the sleeping monsters of Scotland's oil industry are left to rust.

Scotland's oldest medieval bridge is also among the last reminders of early medieval Aberdeen.

The "Bridge Over the Atlantic" lets you cross the waterway in mere seconds.

A labyrinthine network of chambers with a storied past hides below Edinburgh's South Bridge.

Every birth, death, and marriage is recorded in these color-coded leather-bound books.

Built to hold the worst of the worst of the Nazi war prisoners.

Climb this overlooked gem's spiral staircase and you'll be rewarded with spectacular views of Glasgow.

The remains of a grand castle that may have inspired Bram Stoker's Dracula.

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

Ruined castle with subterranean vaulted Goblin Ha' or "Goblin Hall."