Some 80,000 Delft Blue tiles line the inside of this Amsterdam walkway.

Europe's official "zero-level," the equator of elevation.

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

A floating cat sanctuary on an Amsterdam canal.

This gorgeous reading room houses the oldest and largest art history library in the Netherlands.

A beautifully eclectic mix of architectural styles.

This large copper bolt represents the benchmark for measuring sea levels in most of Europe.

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

This bird-loving brewery is situated in an old municipal bathhouse, nestled beside a 300-year-old windmill.

The stately remains of Llywelyn the Great's mighty fortress.

This building's name and a plaque are all that's left of what was probably the most important nightclub of the Madchester music scene.

The little-known second castle that William the Conqueror built in York.

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.

This network of narrow, medieval passages has the most delightful name.

Semaphore saints, a golden dragon's head, and a stone carved with religious warnings all call this cathedral home.

An incredibly well-preserved piece of ninth-century Viking poop.

The National Railway Museum in York is the largest railway museum in the world, attracting almost 1 million visitors per year.

The largest greenhouse in the world is home to over one million types of plants.

400-year-old garden, restored to beauty.

The excellent acoustics of this natural amphitheater made it a popular preaching spot for the founder of the Methodist Church.

A 16th-century artillery fort built to protect England against European invasion.

A quaint hamlet of nine cottages around a small green near Blaise castle.

This haunting stone chasm is a hotbed of mossy rock and English legend.