II.

Land and Resources

Oxfordshire consists of two upland areas: the limestone North Oxfordshire Heights, to the north-east; and the chalky Berkshire Downs to the south. Between them lies a broad vale of rich clay, consisting of the Oxford Clay Vale and the Vale of the White Horse. This Oxford clay formation is exceptionally thick and rich in fossiliferous deposits; grassland predominates. To the west lie the limestone Cotswold Hills and to the east the chalky Chiltern Hills. The Thames flows through the county, joined by its tributaries—the Cherwell, the Evenlode, the Ock, and the Windrush.

Ironstone, sand, gravel, and clay are among the natural resources still worked. Much of the fertile rural area is devoted to arable and sheep farming; the wool trade contributed greatly to the county's prosperity in medieval times. Water from the Windrush was an important source of power for the famous Witney blanket-making industry. There is a large thermal power station near Didcot. The United Kingdom Atomic Energy Authority (UKAEA) research establishment at Harwell is nearby. At Culham Laboratory, near Abingdon, is the Joint European Taurus (JET) project on nuclear fusion. Didcot is a major railway junction.

Oxfordshire has a moderate climate, with an average annual rainfall in the region of 635-760 mm (25-30 in).