The rare discovery of a previously unknown “catastrophic” mass grave containing dozens of men, women, and children is shedding light on just how deadly and widespread the black plague was during medieval times.

Just north of London lies the mass grave at Thornton Abbey, a 30-hectare (74-acre) former monastery complete with a mote. Within its walls, Thornton Abbey is home to a grave containing the remains of at least 48 people, including 21 children, who likely died from the black plague over the course of just a few days and were buried with “great care” in the 15th-century. Each person is carefully wrapped in a burial shroud and laid neatly next to one another in rows, though it is likely there are even more people buried in the grave.

Radiocarbon dating placed the burial at the time of the Black Death, while dental and skeletal analyses determined that children as young as 1-year-old and adults 45 years and older were buried together. Archaeologists analyzed DNA found in the molar teeth of 16 people, which showed evidence for a strain of the disease pathogen Yersinia pestis that is closely related to other mass graves found in London, indicating that they may be a part of the same outbreak.

The black plague devastated England between 1348 and 1349 CE, killing up to half of the population in just two years. Historical accounts and modern surveys tell the stories of how waves of the disease taunted Europe for centuries and resulted in the deaths of more than half of Europeans. Lesser is known about how the highly contagious bacteria impacted rural communities and the measures these small towns were forced to take in order to cope with large-scale death.

Church records indicate a hospital called St. James was located outside the walls of the monastery. During the black death, many institutions were overwhelmed by the sick and dying and were forced to build makeshift burial grounds to accommodate such numbers. It is possible that Thornton Abbey served as a “last resort” hospital for neighboring rural communities seeking help on their deathbeds, a claim that is supported by the grave’s location separate from the church’s burial grounds.

“The hospital run by the canons of Thornton Abbey was the last and only functioning institution where local inhabitants could bring the dead and dying to receive a proper burial and hope for salvation in the afterlife,” write the authors in the journal Antiquity. Even in such dire circumstances, individuals were “buried with respect” at a time when Christianity meant that a “good death” was valued above all else.

1. Y. pestis is spread between people through the air as well as bites from fleas or rats, according to the Centers for Disease Control and Prevention. Recent infections have been reported around the world, including in China and the United States. Today, most forms of the disease are treatable with antibiotics.