Peak District

The Peak District is an upland area in England at the southern end of the Pennines. It is mostly in northern Derbyshire but also includes parts of Cheshire, Greater Manchester, Staffordshire and Yorkshire.
The area has two main parts. The northern 'Dark Peak' is where most of the moorland is found. Its geology is gritstone. The southern 'White Peak' is where most of the population lives: its geology is mainly limestone.
Much of the area is uplands above , with a high point on Kinder Scout of . Despite its name, the landscape generally lacks sharp peaks, but has rounded hills and gritstone escarpments (the "edges"). The area is surrounded by major conurbations, including Huddersfield, Manchester, Sheffield, Derby and Stoke-on-Trent.
The area is very difficult to travel across. The roads are few and narrow. This is due to the terrain, which is hilly, rough and uneven. Major motorways run east and west of the area.
The Peak District National Park became the first national park in the United Kingdom in 1951. It attracts many visitors every year.
Geology.
The Peak District is formed almost exclusively from sedimentary rocks dating from the Carboniferous period. They comprise the Carboniferous limestone, the overlying gritstone and finally the coal measures at the margins of the area. There are outcrops of igneous rocks including lavas, tuffs and volcanic vent agglomerates. The Peak District is like a broad dome (see image below).
Earth movements after the Carboniferous period resulted in the up-doming of the area. This resulted in the dome-like shape. The shale and sandstone were worn away until limestone was exposed. At the end of this period, the Earth's crust sank here which led to the area being covered by sea, depositing a variety of new rocks.
Some time after its deposition, mineral veins were formed in the limestone. These veins and rakes have been mined for lead since Roman times.
The Peak District was covered by ice during at least one of the ice ages of the last 2 million years. Glacial meltwaters eroded a complex of sinuous channels along the margin of the Peak District during this period. Glacial meltwaters helped form many of the caves in the limestone area. Wild animal herds roamed the area, and their remains have been found in several of the local caves.
The different types of rock that lie beneath the soil strongly influence the landscape. They determine the vegetation and so the animals that will live in the area. Limestone has fissures (cracks) and is soluble in water, so rivers carve deep, narrow valleys. These rivers then often find a route underground, creating cave systems. Millstone Grit on the other hand is insoluble but porous, so it absorbs water. Water moves through the grits until it meets the less porous shales beneath, creating springs when it reaches the surface again. The shales are friable and easily attacked by frost. They form areas where landslides may occur, as on Mam Tor.