One of the few remaining casualties of the London Blitz, this destroyed church has become an enchanting public garden.

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

A nearly 500-year-old sculpture depicts a man eating a sack of babies, and no one is sure why.

The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."

The gloomy ruins that inspired Bram Stoker to bring Dracula to life.

Home to items never before seen by the public.

Stalactites and stalagmites in a beautifully lit cave.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

The only swimming pool listed on the National Register of Historic Places is emptied and refilled each day with naturally filtered water.

The beautiful baroque library of the Hapsburg empire.

Thousands of well-dressed mummies below a monastery.

Northern Ireland's Brobdingnagian stepping stones.

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

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

This medieval Italian town is a sheer (and beautiful) cliffside defense.

At the crypt of St. Mary of Eulogies and the Dead you are left alone to ponder mortality among piles of skulls.

This ancient Roman prison is decorated with an upside-down cross not as blasphemy but as saintly tribute.

A museum dedicated to the history and art of staying clean.

Over 600 vacuum cleaners stack the shelves of what may be the cleanest museum in America.

These machines have been collecting dust for decades.

Formerly known as National D-Day Museum, this collection commemorates the battles of Normandy and WWII.

The famous winding walk at Chartres is surrounded in mystery and myth.

Perhaps the most beautiful of preserved saints, with a little help from Paris.

Among the ostentatious rococo ornamentation of this church, an image of death cuts the life-thread.