This London plaque marks the spot where David Bowie's famous alien made his debut.

The wooden telephone box hidden away in London's Piccadilly was the original prototype of the iconic kiosk.

It is still illegal to "quarrel" at this unlikely urban oasis built on top of an electrical substation.

A statue marks the exact spot where The Boy Who Never Grows Up made his first literary appearance.

A unique tribute to the millions of animals who served and died for the British military.

London's last remaining public soapbox site has seen speeches from Karl Marx, Vladmir Lenin, and George Orwell.

A hidden church in a hidden courtyard tells the story of the Miracle of Amsterdam.

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

This 6th-century church has the largest and best-preserved collection of Byzantine mosaics outside Constantinople.

The tomb of the mythological founder of Padua is not hidden in some obscure crypt, but stands right in the middle of the city square.

When this funny little building went up in the 19th century, most people thought it would simply fall over.

The astonishing collection of an infamous criminologist.

A fake medieval village in the middle of Turin.

A sinister pyramid in the Frari contains the heart of the famous neoclassical sculptor.

This curious building hides eclectic details like medieval gargoyles alongside naked angels and Art Nouveau mosaics.

19th-century scientists would make the pilgrimage here to verify the precision of their measuring sticks.

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

Eighty million natural history specimens call this gargantuan museum home.

A 1,000-year-old church holds the bones of the Christian martyrs who died hiding inside it.

The iconic boulevard is the perfect place to catch sight of a bicycling skeleton, a levitating Satan, or a chef with his head stuck in a pizza.

A whale rib was used to advertise the store by the arch that offered exotic goods from far away.

'The Letters of Utrecht' lays out a ribbon of poetry one letter at a time, with no final verse in sight.

As can be expected from a centuries-old church built in a canal city, the undercroft of this house of worship is beautifully flooded.

A new sculpture calls attention to climate change in the centuries-old city it threatens.