[3] The circular form of the moat suggests eleventh- or twelfth-century origins,[4] and the entrance to the site pointed away from the centre of the medieval town at the site now known as the Bull Ring, suggesting that it preceded the twelfth-century development of the town around the marketplace.
[5] Excavations during the construction of the Birmingham Wholesale Markets between 1973 and 1975 revealed a sandstone wall that included a moulding similar to those found on other sites in the West Midlands such as Sandwell Priory, probably dating it to the twelfth century.
[6] This wall had been incorporated into a later structure about 11m long and 4m wide with chamfered ashlar stonework – possibly a tower, an oriel window, the base of a stair or the end of a building – with a buttress that indicates a likely thirteenth century date.
[8] The site was mentioned again in a survey of Birmingham of c. 1529 that describes the moat and a drawbridge and claims that the buildings were in a ruinous condition.
[7] By the time the site was first illustrated in William Westley's 1731 map of Birmingham there appear to have been no medieval buildings remaining apart from a large circular dovecote,[9] and later maps of 1750 and 1778 show four buildings running across the site in a north–south direction.