Sudeley Castle is a Grade I listed castle in the parish of Sudeley, in the Cotswolds, near to the medieval market town of Winchcombe, Gloucestershire, England. The castle has 10 notable gardens covering some 15 acres within a 1,200-acre estate nestled within the Cotswold hills. Building of the castle began in 1443 for Ralph Boteler; the Lord High Treasurer of England, on the site of a previous 12th-century fortified manor house.