William the Conqueror found the monastery in a state of decay and he appointed the first Norman abbot, Serlo, in 1072. Serlo started major rebuilding work in 1089 that lasted until he died in 1104. The abbey church he built was consecrated in 1100. When Serlo died, in 1104, he was succeeded by Prior Peter and during his reign, the abbey church was given many donations of land. One of these being Robert Curthose, William the Conqueror's eldest son. An effigy of Robert can be seen in the Cathedral. The abbey also became an important Benedictine house in this century.
Above is a photograph of the Great Cloister. Normally cloisters are normally built to the south of the church but in this case they lie to the north. This may have been because of a lack of open space to the south. The cloisters may have been rebuilt between the middle and late 14th century and contain the first fan vaults to be seen in Britain. Fire played its part in the development of the abbey as the original Norman church had a wooden roof and was under constant threat. The abbey church was under constant financial threats as the cost of maintaining and adding to the building was so high. In 1284, John de Gamages became abbot at Gloucester and through his farming knowledge increased the stocks of sheep owned by the abbey and returned a profit. After de Gamages reign things again took a down turn, until the death of King Edward II. The King was buried at Gloucester and the number of pilgrims that visited the abbey gave it a much needed boost. Gloucester Cathedral was used as a location for Hogwarts in the Harry Potter film Harry Potter and the Philosopher's Stone.