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Secret rooms and hidden doors are generally considered features of haunted houses, but in 16th-century England, they were integral in keeping Catholic priests, and Catholicism itself, alive. With the Protestant Reformation ramping up and Catholicism under attack, a system of safe houses equipped with cleverly hidden “priest holes” kept fugitive clergymen safe from persecution.

When Protestant Queen Elizabeth I ascended to the throne in 1558, the anti-Catholic attitude among much of the British monarchy had reached fever pitch. Elizabeth immediately became the target of a number of Catholic church plots aimed at removing her from the top spot.

The queen’s response to these plots was not subtle. Under her rule, it became illegal to practice the Catholic faith in England. Anyone found engaging in Catholic rituals could face punishments ranging from fines to life imprisonment.

Catholic priests were in even more danger. It became high treason (which was often punishable by death) for a Catholic priest to so much as enter England, and anyone found aiding or harboring a priest would be just as guilty. The same went for anyone caught attempting to convert someone to the faith, as it was seen as removing supporters from Elizabeth’s cause.

Needless to say, it was hard out there for a priest. But they and their congregants had crafty ways of coping. Devout Catholics living under Elizabeth’s reign began to worship covertly, establishing a network of homes for priests and other “recusants” to continue the faith in England. Secret symbols, like wax discs bearing a cross and a lamb (representing the Lamb of God), were used to mark safe houses. Jesuit priests were smuggled into the country, coming to live with faithful families under the guise of a visiting teacher or cousin.

Of course, the crown got wise to these covert operations and began sending out priest hunters (technically called pursuivants) to ferret out the treasonous clergy. Surprise inspections and raids of wealthy family homes were not uncommon. If a priest was found, he would face torture and eventual execution.

To escape this fate, a number of homes installed hidden compartments called priest holes, where Catholic leaders could conceal themselves in the case of an inspection. These small hideaways were often built under staircases or inside fireplaces or behind false walls. (Even if you weren’t harboring a religious fugitive, the priest holes made a great place to stash your candles, crucifixes, and other Catholic accoutrements.) Some homes would have multiple priest holes scattered throughout, with at least one, Hindlip Hall, maintaining 12 separate holes. Some priest holes would even be hidden behind secret panels in other priest holes as an added precaution. The hiding places were generally very small, with barely enough room for a full-grown adult to fit, but they did the trick.

Priest hunters eventually got wind of these clever holes and stepped up their searches accordingly. They would knock house walls to see if they were hollow or measure the footprint of the building on the inside and outside to see if they matched. They began counting the windows and pulling up the floors. Sometimes they would stake out a home for days or weeks, just waiting for a Catholic priest to pop his head out of his hole. Occasionally, priests even perished in their hidey holes after they were unable to emerge for food or water. (To combat this, some priest holes featured hidden feeding tubes).

Due to the secret nature of the holes, there is no record of exactly how many were built. But one man stands out as the master of the craft. Jesuit brother Nicholas Owen, nicknamed “Little John” thanks to his height, began designing and building hidden chambers around the 1580s. For the next 20 years he turned hiding priests into an art. A master architect and builder, Owen was known for his ability to create secret chambers that baffled the priest hunters.

Owen was almost found out a number of times during his career and got arrested and tortured in 1594. But even when subjected to agony, Owen never gave up the location of another priest or the holes he built. When was caught a final time in 1606, he gave himself up to distract from other priests hiding in the house. He was taken to the Tower of London and tortured to death, never giving an inch. For his work in creating the priest holes that saved countless lives, Owen was sainted by Pope Paul in 1970 and is now known as the patron saint of illusionists.

Today, many examples of priest holes still exist in historic English manors like Harvington Hall and Naworth Castle. The old wood planks can still be pulled aside, revealing the cramped spaces that helped Catholicism endure a troubled time.

This is a modified version of an article that ran previously on Atlas Obscura.

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