The block of aged dairy is probably still edible after 2,300 years in a peat bog.

A 'living museum' in Leiden, the oldest of its kind in the Netherlands.

A massive explosion that leveled hundreds of buildings in the city of Leiden is remembered by a waterside plaque.

The alpine falls where Sherlock Holmes apparently met his demise can actually be visited.

This historic covered bridge contains a series of macabre paintings that communicate one thing: everyone dies.

This memorial commemorating fallen Swiss Guards of the French Revolution has been called the saddest stone in the world.

Bell tower juts out from a village buried under a lake.

A map of Italy made entirely of trees.

These pillars at the main entrance of this church are actually a hidden musical instrument.

On La Gomera, "Silbadors" communicate in a 4,000-word language of whistles.

A shrine-like museum entirely dedicated to soccer superstar Cristiano Ronaldo.

A lush oasis full of vibrant plants and striking geometric displays.

These small, triangular, colorful houses are a staple of Madeira Island.

This astronomical clock is the second oldest in England.

Fascinating town where normal life interfaces with the occult.

This hill and tower are steeped in legend, from King Arthur to the Holy Grail.

Inspired by Thomas Stothard's painting of the "Journey to Canterbury," albeit with Canterbury natives.

One of England's most famous churches hides a pair of little known architectural treasures.

A open air theatre built on a cliff by an eccentric British woman.

Sometimes an island, sometimes a rocky outcropping connected to the world by a tiny suspension bridge.

It is said the legendary wizard once lived in this sea cave beneath Tintagel Castle.

A whimsical cottage from the 1300s with a preserved Victorian-era post office inside.

A fantastic castle rumored to be the birthplace of King Arthur.

This short white tower is all that's left of Scotland's first permanently manned lighthouse.