Archaeologists in Oxford have unearthed the remains of 92 people, including a number of “sex-crazed” nuns, in the burial grounds of Littlemore Priory, a former nunnery founded in 1110, the Daily Mail reports.

According to the experts, 35 of the bodies were female, 28 were believed to be male, and in 29 cases it was impossible to determine a gender.

Archaeologists released pictures of the grisly discovery this week, explaining that some of the bodies were buried upside down, a “mark of shame” that has lead them to believe that they had been responsible for lewd, or immoral behavior. So-called “prone burials” are thought to have been reserved for witches or sinners.

Believed to be 600 to 900 years old, the bodies of the “sinner nuns” were discovered near Oxford United football stadium, and next to a hotel.

“We knew the church was there and we knew we would find something, but the number of burials was a real surprise,” investigation leader Paul Murray, from John Moore Heritage Services, told Express. “The number and range of burials is the most useful and gives us the chance to look at the diet of nuns, which hasn’t really been studied before,” he added.

Eileen Power’s book Medieval English Nunneries (1922) describes the place as “one of the worst nunneries of which records survived.” This was reportedly due to a bad prioress, named Katherine Wells, who oversaw much scandal and mothered an illegitimate child with a local priest.

Another report, written in 1445 and quoted in the Daily Mail, said the sleeping quarters were “’so ruinous the nuns were afraid to sleep there” and “that the nuns were sleeping two to a bed, with even the prioress having to share her bed. ”

The sins committed were so grave by medieval standards that the nunnery was permanently shut down in 1542 by one time adviser to King Henry VIII, Thomas Wolsey, who made the final call.

Surprisingly, this is not the first curious old burial discovered in recent times (see Archaeologists Find Prehistoric Lovers Locked in Embrace for 6,000 Years and French Archaeologists Discover Ancient Chariot Tomb).