St Gregory's is Sudbury's most historic church, founded in the fourteenth century by Simon of Sudbury — the Archbishop of Canterbury who famously met his end in the Peasants' Revolt. The building is an important example of Perpendicular Gothic with some striking medieval details, including a fine carved font.
The church is usually open for visitors during daylight hours. The mummified head of Simon of Sudbury, which has been kept here since the Revolt of 1381, is the most remarkable artefact — though it is kept in a wooden cabinet and only occasionally displayed. The church sits in a quiet corner of the town, a short walk west from Market Hill.