A sacred well steeped in Pagan roots on the West Coast of Ireland.

This Irish museum in a historic 19th century market pays tribute to the glory of butter.

This amazing abuela became a diehard metal fan late in life and an icon of Madrid's '80s rock scene.

The London pub overlooks where the Mayflower was moored before setting sail for the New World.

The monster at the center of the Darwin Center Spirit Collection.

This cafe offers a curated collection of treats and tipples made by monks and nuns.

The iconic boulevard is the perfect place to catch sight of a bicycling skeleton, a levitating Satan, or a chef with his head stuck in a pizza.

Catacombs turned marketplace.

The perfectly preserved underground rooms where Churchill plotted the war against Germany.

A church of bones, decorated with 40,000 human skeletons.

Hanging within this medieval church are the bones of a beast allegedly slain by a fourth-century saint.

Once the home of a hermetic monk, this cave now houses a small church.

A series of caves under Castle Hill that once held the prisoner Vlad Tepes, better known as Count Dracula.

A museum in the childhood house of a medical pioneer.

A sulfuric hellscape in southern Italy.

With over 100 jam-packed rooms to explore plus elaborate tea services and events, the Mansion on O Street is a hidden treasure.

This whimsical park encourages its visitors and wildlife to roam on and around the various works of art.

A medical facility that has been kept frozen in time.

This former Roman Catholic Church still contains the embalmed hearts and organs of 22 popes.

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

Since 1887, this old-school shop has stacked its shelves with extraordinary coffees and teas.

The medieval woodcut-style artwork chronicles life in medieval London.

This coffee shop lies hidden beneath a historic church.