A rich diversity of landscape areas exist across West Sussex. The distinctive Wealden Greensand ridge, formed from deposited sands and clays when this part of Britain was under the sea, shares the same sloping landform as the chalk hills. River valleys support wetland habitats and wildlife. Lowland heaths provide shelter and breeding grounds for reptiles and heathland insects. Ancient woodlands, beech plantations and mystical yew groves offer secluded habitats for specialist species.