Over two centuries old and counting, Madrid's massive botanical garden contains one of Europe's only desert environments.

An ancient Egyptian temple in the middle of Madrid, Spain.

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

This castle resides in a valley known for immense bloodshed during the Middle Ages.

This site contains overlapping ancient graveyards that existed about 1,000 years apart.

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

This extraordinary Viking artifact has traveled throughout the city.

A close look reveals that the Scottish monument is just slightly off-kilter.

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

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

The heart of a Scottish legend had a centuries-long journey before reaching its final resting place.

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

Protecting the dead from opportunistic body snatchers.

Overlooked by many, the two famous Scottish warriors guard the main gate of Edinburgh Castle.

More stones than Stonehenge, all scattered within a windswept landscape sure to enchant 'Outlander' fans.

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

A mysterious monument where a woman who records say never existed was burnt alive for being a witch.

Possibly the oldest of Britain's ancient henges is also one of its most stark.

Largest lake in Great Britain measured by surface area.

This modern labyrinth lies in the shadow of a ruined medieval castle.

The one-time stronghold of the noble Douglas family, now home to ghost sightings and nesting birds.

The heads of two giant mythological water horses honor Scotland's horselord past.

The mysterious megaliths have enchanted and intrigued visitors for thousands of years.

On this stunning Scottish island, you can walk in the footsteps of dinosaurs.