The church was greatly enlarged in the 14th century with addition of an ambulatory to the east end.
In the 12th and 13th centuries, the abbey fostered the successful writers Robert of Cricklade and Alexander Neckam.
They were supported in their work by other canons, including Walter of Mileto and Alexander's nephew Geoffrey Brito.
The area that contained the nucleus of the monastery is now a public park, and only the Norman Arch, an original gateway to the abbey, and parts of the precinct wall remain above ground.
The impressive and substantial three-storey porch of the parish church was built as an administrative building of the abbey and after 1539 the upper levels were used for some time as the town hall.