The sign at the garden gate reads: "These Plants Can Kill."

A neo-Gothic church built to thank God for saving the Emperor of Austria from an assassination.

This Austrian museum celebrates the work of famous forgers and their inimitable imitations.

The crypt of the imposing Stephensdom holds royal intestines and thousands of skeletons.

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

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

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

The hallucinogenic center of the ancient world.

The final resting place of the poets Shelley and Keats.

Pompeii's less famous neighbor is still revealing her secrets.

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

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

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

Behind the pink curtain, Au Bonheur du Jour, an art gallery of erotic archives.