A monastery near Salisbury, named after its abbot. In Geoffrey’s chronicle, it was the location of a battle between Vortigern’s Britons and Hengist’s Saxons.
The two sides had convened to sign a peace treaty, but the Saxons betrayed the Britons and attacked. Eldad, the bishop of Ambrius, buried the victims of the battle.
Source
Historia Regum Britanniae | Geoffrey of Monmouth, c. 1138