Andersey Island is one of the largest islands on the River Thames. It is bounded on one side by
the Thames, and on the other by Swift Ditch. The island was once the site of a royal residence as
early as Anglo-Saxon times, and was taken over by William I. The site was handed over to the Abbot
of Abingdon around 1100 and the buildings fell into ruin. Materials from the ruins were used by
the Abbot to rebuild the monastery. Most of the island is now open land.