A short walk south of the town centre, the ruined nave of St Botolph's Priory rises out of the lawn behind a Georgian terrace. The priory was founded around 1100 and was the first Augustinian house established in England — the order would go on to found over 200 priories across the country. The west front, with its great Norman archway and tiers of round-headed window arches, gives a vivid sense of the building's original scale.
The priory was wrecked during the 1648 siege of Colchester, when Parliamentary cannon battering Royalist defenders blew out the nave roof; the ruined shell has stood since. The remaining stonework is a mix of reused Roman brick from the nearby walls and dressed twelfth-century masonry. Free to enter; the surrounding churchyard makes a pleasant lunch stop.