Excavation by R J Poulton for SyAS, SCAU and Guildford Borough Council in Castle Cliffe Gardens located a large deep ditch which had probably been largely infilled by the early 13th century. It is postulated that it was the original outer bailey ditch, filled in when the Castle was extended further south to the Quarry Street line in the 13th century, for the Royal Palace. In the area of the Palace the corner of a well-constructed building thought likely to be Lord Edward's Chamber of 1246 was found, and a large deep feature thought to be of 12th century date and to have an industrial function awaits further investigation. (250; 251; see Guildford Castle monograph)