One of the most important historic monasteries in East Anglia, this English Heritage site is home to the extensive remains of Thetford Priory. Founded in the early 12th Century the priory gained fame after a reported sighting of the Virgin Mary, and drew wealthy pilgrims from across the country that donated generously to the extensions that were made to the structure. Sadly, much of the priory eventually fell into disrepair, but the lower walls and the cloister are still clearly visible today.