This Norman castle was once the site of a Victorian-era prison, and now exists as a luxury hotel.

A theatre built to house the rowdy Oxford graduation ceremonies became the stage for a debate about God's existence.

Once one of the largest rooms full of books in the world, this bookstore basement is still a treat for bibliophiles.

An extraordinary collection of scientific instruments - and Einstein's chalkboard - inside the world's oldest purpose built museum building.

A rare specimen of the ancient piggy bank of Java resides in one of the unassuming corners of the Ashmolean.

One of Oxford's greatest treasures likely belonged to the legendary King Alfred the Great.

Used as an example in one of the first dictionary entries for "museum" in 1706.

A little piece of Oxford's overlooked industrial heritage.

This medieval manor house was equipped with secret compartments for hiding priests.

An ancient passage filled with stalls selling used books, once frequented by Vincent Van Gogh.

An Amsterdam street lined with antique shops each one dedicated to a different obscure collection.

Debatably clever, or just plain honest hotel advertised as "The Worst Hotel in the World."

This small town in the Netherlands has no roads but instead, miles of canals and over 100 bridges.

A Dutch clog company in the town of Zaandam loves the wooden shoes so much it made a museum for them.

Tucked in the back of a flower shop, its collection details the fascinating history of the Netherlands's iconic symbol.

A public urinal so pretty, it was declared a national monument.

A Dutch passageway's artistic, aquatic-themed makeover pays tribute to the capital city's famed waterways.

Amsterdam's narrowest house facade is a monument to 17th-century tax evasion.

Established in 1638 to battle the Black Death, Hortus Botanicus Amsterdam is a treasure trove of rare flora.

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

This sculpture marks the spot where one of the greatest Roman rulers was proclaimed emperor.

This popular square's history as the former site of a church is right beneath your feet.

One of the shortest streets in York has an especially odd name.

Follow the original medieval paths that wind through this intriguing section of the city.