On rare days, this abandoned castle's gatekeepers open its doors, revealing the eye-popping splendor hidden inside.

A blend of art, antiquities, and Americana fill this museum, surrounded by whimsical, enchanting gardens.

A public park off the beaten path with a beautiful waterfall and 13th century Cistercian abbey.

The only remaining collection of flayed figures made by French "madman" Honoré Fragonard.

Museum in a swimming pool where the water still flows.

This former limestone quarry is now a subterranean wonderland of grand stonework.

The 16th-century church was kept in its ruined state as a reminder of the casualties of World War I.

A small world of mechanical magic and metal merry-go-rounds in a Outsider art Museum.

The somewhat misnamed 'Garden of Shells' lovingly built from found objects.

Sacked by Vikings, blessed by William the Conqueror, dealt a fatal blow during the French Revolution—these ruins have seen it all.

This artist's home turned gallery/museum preserves the creator's love of "Eastern" influences.

A curious little museum dedicated to the furry feline in the cat haven that is Old Town Kotor.

Trace the history of writing at this unusual North Carolina destination.

Hundreds of antiquated typewriters and office machinery show the technological evolution of business.

The home and studio of a visionary woodworker now stands as a museum and example of his artistic genius.

Arlington Cemetery exhibit dedicated to death and grieving.

An abandoned cemetery lies in ruins as the surrounding forest swallows it whole.

This stunning French estate was so lavish that it landed its original owner in jail for the rest of his life.

A preserved factory in the "Home of the Carrousel" is now a museum dedicated to the classic wooden ride.

A mosaic-tiled house built by graveyard sweeper Raymond Isidore.

The Church of the Annunciation was carved into the face of a cliff, just like the rest of the town of Haute-Isle.

A former milk-delivery driver and his wife turn their home into a glimmering mosaic.

Hidden away in a modern library are the remains of one of the 18th century's most celebrated wunderkammers.

This fairytale castle was built as a show of power but was nearly torn down thanks to its history of torture.