Hereford Castle was a castle in the cathedral city of Hereford, the county town of Herefordshire, England (). Founded sometime before 1052, it was one of the earliest castles in England. Hereford Castle was probably destroyed when the Welsh sacked Hereford in 1055, but seems to have been replaced by the following decade. During the civil war of King Stephen's reign, the castle was besieged three times; the garrison surrendered each time and control of Hereford Castle changed hands.