St Augustine's is the Catholic church of Abbeyside, on the east bank of the Colligan. It was built in 1832, but it incorporates the tower and nave of the 13th-century Augustinian friary founded by Thomas FitzMaurice FitzGerald, which gave Abbeyside its name. The friary was wrecked in the Cromwellian period.
It's a pleasant stop on a walk along the east bank, where Sexton Street and Walton Park have the best views back across the estuary to the town.