Following the withdrawal of the Roman administration, the site is thought to have been in use from until some time after 580. Alcock revealed a substantial "Great Hall" and showed that the innermost Iron Age defences had been refortified, providing a defended site double the size of any other known fort of the period. Shards of pottery from the eastern Mediterranean were also found from this period, indicating wide trade links. It therefore seems probable that it was the chief "caer" ("fort") of a major Brythonic ruler, his family, his "teulu" (literally meaning "family", but actually meaning "warband"), servants, and horses.