Geology is important to the Land of Oak & Iron because it has provided the coal, iron ore, water power and timber that have created the local landscape and industries.
Most of the rocks are from the Carboniferous Period, when this area was usually covered in tropical forests. The oldest of these rocks, at Shotley Bridge and upstream, are quite hard and were used to make millstones for grinding corn. In these same strata are the ironstones which were used in the early days of our iron and steel industry.
Lower down the Derwent Valley, the coal seams are thicker and more frequent. This coal fuelled the early industrial processes and produced the enormous wealth of the local landowners. It has left us a heritage of disused waggon ways and railway lines, most notably the Derwent Walk.