We have suggested to identify the town of Hazza, which was designated by Ibn Hawqal in the tenth century as being the eponym of the whole Arbīl province, with both the Sasanian town of Būdh Ardašīr and the later Islamic toponym of Kafr ‛Azzā/Kfar ‛Ūzaīl. The town took over certain functions from the traditional centre of Arbīl, also becoming an important centre of Christian settlement, administration, and pilgrimage, along with the nearby monastery of Mār Mīkhā’īl. The gradually Islamized centre lost its importance in the middle Islamic period. The location of Hazza/Kafr ‛Azzā may be associated with an extensive site stretching between the villages of ‛Azza and Qūnyān, 12 km WSW of Arbīl. The site comprises dozens of low, heavily ploughed-up mounds surrounding a medium-sized central tell. According to the survey results, the beginning of the settlement can be dated to the Sasanian period and the built-up areas reached their full extent (c. 103 ha) during the seventh and eighth centuries. In the subsequent phase, the central tell appears to have been abandoned, with the site gradually reducing in size and eventually being abandoned in the sixteenth century. Surface finds of blue-glazed tiles corroborate an existence of an important, decorated architecture on the site.