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On the sign:
The Black Assize - hunderds die of gaol fever 1577 OXFORD PRESERVATION TRUST
Station No. 8 in the historic Oxford Castle route, consisting of 14 plaques depicting landmarks on the site from 700 AD to 2006
The name was given because of an epidemic in which hundreds died of typhus, but it was widely believed that the death was that of all those involved in the trials at Oxford Castle, except the prisoners themselves.