A sea cave with a waterfall and Viking past

One of Edinburgh's oldest pubs hides a 19th-century skittles alley in the back.

This beach runway is off limits during high tide.

This 1,300-year-old marker is one of the finest and most complete early Christian crosses in Scotland.

Scotland still bears an enormous scar of its Roman past.

A secret door leads to this cozy dive that sells only “milk.”

The last manually operated turntable ferry in the world.

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

This Scottish castle has witnessed clan rivalries, Jacobite uprisings, whisky smuggling, and more.

These mysterious religious carvings were once thought to be thousands of years old but are actually the work of modern eccentric.

Small museum dedicated to the founder of electromagnetic theory.

This seaside Scottish holiday rental lets you live out your bookselling dreams.

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

The 5,000-year-old megalith is believed to be Scotland's tallest standing stone.

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

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

Sprawled across the Great Hall ceiling are various constellations and images relating to the zodiac.

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

Legend says this rock was once a chopping block for public executions.

The community pools that the community refused to give up on.

A trio of giant megalithic stones in the middle of a golf course.

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

The ruins of a medieval seminary some say is the oldest university site in Scotland.

The discovery of this Neolithic settlement, which contained a Stone Age "cathedral," threw archaeologists for a loop.