A historic observatory now an astronomy museum beautifully situated at the moat of the Middle Age city centre.

This Netherlands museum holds a gloriously mechanical collection of ornate musical automata.

There might not be much left of these Irish ruins, but their linguistic legacy is still going strong.

A Cuban artist reclaimed his impoverished neighborhood as a dreamy folk art kingdom.

Cuba's historical trains remind natives of their country's sugary sweet past.

A bronze sculpture of Lenin’s likeness outside Havana surrounded by 12 human figures in solidarity with the Bolshevik Revolution.

A Spanish-style estate that has traded black ties for rock concerts.

Castro's communist ice cream mothership has been serving five-scoop "salads" for over 50 years.

In terms of history and architecture, this is one of the most remarkable cemeteries in the world.

An ossuary built in 1210 to collect bones from the Ospedale Maggiore of Milan.

The world's only museum devoted to the wonders of fluorescence.

A poignant museum dedicated to the history of the Dutch resistance against Nazi occupation

Oldest Museum of the Netherlands is a true cabinet of curiosities.

This massive mural by famed pop-artist Keith Haring was hidden for almost 30 years until its 2018 rediscovery.

Famed for its pie, this eatery has a hidden tunnel that allowed Catholics to secretly walk to church during the Reformation.

A mud statue stands in the dark tunnels, seeming to hold up the weight of the city above.

A Parisian exterminator's shop whose storefront displays stuffed rats hanging from traps.

Pitié-Salpêtrière was the dumping grounds for women who received the dreaded diagnosis of "hysterical."

This former “ante-chamber to the guillotine” has been refurbished to illustrate the brutal history of French justice.

Skeletons, medical artifacts, and other obscure and precious treasures all displayed in a wooden pharmacist's cabinet.

A modern-day Lascaux cave underneath Paris.

The curious underground history of keeping Paris clean.

Original cabaret handbills, posters, and feline artwork are a purrfect highlight of the Museum of Montmartre.

The subterranean "lake" below the Paris opera house inspired the Phantom of the Opera's lair.