Cirencester is a market town and civil parish in the Cotswold District of Gloucestershire, England. Cirencester lies on the River Churn, a tributary of the River Thames. It is the eighth largest settlement in Gloucestershire and the largest town within the Cotswolds. It is the home of the Royal Agricultural University, the oldest agricultural college in the English-speaking world, founded in 1840. The town had a population of 20,229 in 2021.