The area around Braintree, like much of Essex, is predominantly flat, lying at about 50 metres above sea level. To the north the countryside is dominated by arable farming, and as you move south it gradually becomes more urban, housing and factories predominating as you get closer to London. Its main geographical features are two river valleys – the River Pant becomes the Blackwater as it skirts Braintree itself, then flows close to Coggeshall, Kelvedon and Witham before joining the estuary at Maldon, and the River Colne flows through Halstead on its way to Colchester. It has a scattering of ancient woods, and notably a fine group of woods at Marks Hall, with Broaks Wood, Chalkney Wood and Brookes nature reserve not far away. A few new wildlife sites have been created near the urban centres of Braintree, Witham and Kelvedon, and Essex Wildlife Trust manages two nature reserves near Great Leighs and one in the far north-east.