Slate covers most of the northern portion of the mountains, and thick beds of lava are found in the southern part.
Other sedimentary layers have yielded chains of hills ranging from 965 feet (294 metres) in the North Downs to 1,083 feet (330 metres) in the Cotswolds.
The oldest sedimentary rocks and some igneous rocks (in isolated hills of granite) are in Cornwall and Devon on the southwestern peninsula, ancient volcanic rocks underlie parts of the Cumbrian Mountains, and the most recent alluvial soils cover the Fens of Cambridgeshire, Lincolnshire, and Norfolk.
Between these regions lie bands of sandstones and limestones of different geologic periods, many of them relicts of primeval times when large parts of central and southern England were submerged below warm seas.
Plateaus of limestone, gritstone, and carboniferous strata are associated with major coalfields, some existing as outcrops on the surface.
The geologic complexity of England is strikingly illustrated in the cliff structure of its shoreline.Deep deposits of sand, gravel, and glacial mud left by the retreating glaciers further altered the landscape.Erosion by rain, river, and tides and subsidence in parts of eastern England subsequently shaped the hills and the coastline.Yet commonalities are more important than these differences, many of which began to disappear in the era after World War II, especially with the transformation of England from a rural into a highly urbanized society.The country’s island location has been of critical importance to the development of the English character, which fosters the seemingly contradictory qualities of candour and reserve along with conformity and eccentricity and which values social harmony and, as is true of many island countries, the good manners that ensure orderly relations in a densely populated landscape.The Welland river valley forms part of the rich agricultural land of Lincolnshire.The Thames, the longest river in England, also rises in the Cotswolds and drains a large part of southeastern England.The hills known as the Chilterns, the North York Moors, and the Yorkshire and Lincolnshire Wolds were rounded into characteristic plateaus with west-facing escarpments during three successive glacial periods of the Pleistocene Epoch (about 2,600,000 to 11,700 years ago).When the last ice sheet melted, the sea level rose, submerging the land bridge that had connected Great Britain with the European mainland.Cotswolds, and the moors and chalk downs of southern England serve as watersheds for most of England’s rivers.The Eden, Ribble, and Mersey rise in the Pennines, flow westward, and have a short course to the Atlantic Ocean.