Pennines  and limestone  hills of the  Peak District ,  Exmoor  and  Dartmoor . The main rivers and estuaries are the  Thames ,  Severn  and the  Humber . England's highest mountain is  Scafell Pike  (978 metres (3,209 ft)) in the  Lake District . Its principal  rivers  are the Severn, Thames, Humber, Tees, Tyne,