These quaint cottages feature built-in signaling devices for fishermen.

An iconic red telephone box turned tiny art gallery.

An abandoned, desolate train tunnel that was used during World War II.

Nestled among the living residents is the final resting place of an apothecary plague victim.

A sea cave with a waterfall and Viking past

This stately bank building hides a spectacular star-studded ceiling.

The abandoned transportation hub hides within the Glasgow attraction it once served.

These ruins of a medieval church are full of architectural mysteries.

The 20th-century chapel’s intricate woodwork includes amazing details, most notably angels playing bagpipes.

It's a mystery how these curious columns wound up in an Edinburgh suburb.

A series of three shiny letters mark the boundary of an old refuge for those being pursued by debt collectors.

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

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

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

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

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

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

Come for the oysters, stay for the priceless art honoring inventors across history and Scotland's favorite outdoor sports.

This obscure walkway links Edinburgh’s Old Town with one of the city's prime vantage points.

This single-track road rewards brave drivers with stunning Scottish scenery.

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

A verdant 17th-century-style garden hidden along Edinburgh’s Royal Mile.

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

The ornate structure is part of a building boasting more marble than the Vatican.