An encyclopedic collection of mammal penises.

The hidden "ballroom" under a mansion lake was built by a criminal who ate a cyanide pill during his trial.

Rebuilt remains of a temple to Roman god Mithras.

Two beautiful Victorian-era parks replete with ornamental waterfalls and lakes.

This coffee shop lies hidden beneath a historic church.

A special shop catering to the needs of things that go bump in the night, and also helps kids become writers.

One of the best beaches in the entire world.

Inside this Icelandic greenhouse, geothermal energy keeps tomatoes warm and growing.

This tiny museum's sizable collection is jammed into a former underground public toilet.

Eerie ruins of an abandoned medieval fishing village crumble atop an unforgiving stretch of earth.

Walk in the footsteps of the gods and straddle two tectonic plates.

The taxidermy remains of the first mammal ever cloned from an adult cell are on display in Edinburgh.

Prehistoric sandstone menhir with Early Bronze Age cup and ring markings, also known as Robin Hood's Stone.

19th century tunnels burrowed under Liverpool.

An ancient stone with mysterious origins stands in a residential neighborhood.

A remnant of the Roman army's presence on the coast of Scotland.

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

A pair of stones embedded in an Edinburgh street memorialize one of the city's last public hangings.

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

Enter this small nook and you'll be surrounded by 360 degrees of street art.

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

A succession of eerily contemplative iron figures lead from a Scottish museum to the sea.

A library where thousands of books explain how to avoid another Great Recession.

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