In Wessex a number of the burhs which were part of the system recorded in the Burghal Hidage, and which were merely fortresses rather than fortified towns, were in many cases replaced at a later date by larger fortresses which were fortified towns. The received view of the date of this process is that this took place in the 920s or 930s during the reign of King Athelstan. More recently, arguments have been given which places these changes in the reign of Alfred, possibly in the 890s in response to the new Viking invasions. Examples of this process can be seen in the replacement of Pilton by Barnstaple, and Halwell by Totnes and Kingsbridge in Devon.