Cuffley Brook is a tributary of the River Lea in Hertfordshire, England.Cuffley Brook is one of the longest brook tributaries of the Lea, forming from Grimes Brook north west of Cuffley, Northaw Brook south-west of Cuffley, snaking for several miles through the south-east Hertfordshire hills past Crews Hill until it reaches a confluence with Turkey Brook, in the London Borough of Enfield, near Forty Hall.