Where is the Stour Valley? The Stour Valley in on the county boundries between Essex and Suffolk, about an hour away from London. The main road to the area is the A12 from London, and there is a good railway connection from London. The closest main towns are Colchester and Ipswich. The Local Map shows the area in a little more detail - you are in Constable Country, with the villages of Flatford, Dedham and East Bergholt only minutes away from Manningtree and Mistley.