Medieval museum built over Roman baths that features famous tapestries of a lady and a unicorn.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

An overlooked marble is the only surviving in-place 18th century example of the measurement that changed how we define distance.

This abandoned five-star hotel is now a five-star urban exploration destination.

A 19th-century mansion houses the largest collection of gin in the European Union.

One artist's collection of homemade handicrafts doubles as a monument to 20th-century material culture.

This fairy-tale, neo-Gothic church in the Azores is a world of magical realism.

Bits of flat terrain surrounded by cliffs make one of the most beautiful landscapes in the Azores.

On the cliffs of São Jorge in the Azores stand the remains of a lighthouse that was struck by a series of earthquakes.

World's first "penitentiary," meant to be humane, drove men insane.

This museum inside Amsterdam's largest cemetery explores how people deal with death.

A rare tour of an aristocrat's private home reveals valuable 17th-century paintings from artists like Rembrandt.

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.

Amsterdam's former hotspot for public executions and dissections.

The last of Amsterdam's original sea level markers remaining in place.

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

This impressive collection of rare books on ancient mysticism inspired author Dan Brown.

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

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

A unique work of automotive art calls this shopping center home.

Decades after testing the polio vaccine on unwitting patients, this historic mental hospital sits in ruin.

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

This museum housed in a former brothel explores the past and present of sex work in Amsterdam.