The remains of more than 240 people, including children, have been unearthed by archaeologists working on the remnants of a medieval priory found beneath a former department store.
The "hugely significant" discovery was made under the old Ocky White building in Haverfordwest, Pembrokeshire.
Archaeologists believe the ruins are from St Saviour's Priory, founded by a Dominican order of monks in about 1256.
One expert said it offered a "window into medieval Haverfordwest".
Ocky White was a popular store for more than a century before its riverside premises closed in 2013.
