The River Lea and its crossing at Hertford lie at the heart of the town's history. Before the Norman Conquest the river formed a natural boundary between the Danelaw to the north and Saxon Wessex to the south. Saxon villages already existed at Bengeo and Hertingfordbury and, in 911 and 912, Edward the Elder, son of Alfred the Great, founded two fortified burhs, north and south of the Lea crossing. Following the Norman Conquest a castle was established...