A hotel now stands near where the River Foss joins the River Ouse but 500 years ago the site was occupied by St Andrew's Gilbertine Priory. Excavations by York Archaeological Trust in the mid 1980s uncovered the remains of the priory and revealed its history from its foundation in 1195 to its dissolution in 1538.

The dissolution of the monasteries brought about the ruination of most of the great monastic houses in the kingdom. Like so many others around the country, the buildings of St Andrew's Priory were demolished and robbed of re-usable building materials.

The lead from the roofs and from the strips which held the painted glass together in the windows (lead came) was of particular value. A heap of glass fragments was excavated in the chapter house, possibly where the glass had been ripped from the lead, the lead-strippers working where once the canons had held council. Other heaps of glass were found in the nave of the priory church.

Approximately 50,000 fragments of glass were recovered making this the largest collection of glass from a Gilbertine priory. It had deteriorated badly in the wet conditions and offered a considerable challenge to conservators. Since little had been published on how to deal with wet archaeological glass, this provided a great opportunity to test some innovative ideas. It was an important collection and likely to attract wide interest, so another objective was to devise a means of packaging and storage which would allow the glass to be studied without causing further damage.