Geographical outline OF THE UK

The total area of the United Kingdom of Great Britain and Northern Ireland is approximately 245000 km² comprising of the island of Great Britain, the northeastern one-sixth of the island of Ireland (Northern Ireland) and smaller islands. It lies between the North Atlantic Ocean and the North Sea to the northwest from the coast of France. It is separated from France by the English Channel. The Royal Greenwich Observatory, near London, is the defining point of the Prime Meridian. When measured directly north-south, Great Britain is a little over 1100 km in length and is a fraction under 500 km at its widest, but the greatest distance between two points is 1350 km between Land's End in Cornwall (near Penzance) and John o' Groats in Caithness (near Thurso). Northern Ireland shares a 360 km on land boundary with Ireland.

The United Kingdom has a temperate climate, with plentiful rainfall all year round. The temperature varies with the seasons but seldom drops below 10°C or rises above 35°C. The prevailing wind is from the southwest, bearing frequent spells of mild and wet weather from the Atlantic Ocean. Eastern parts are most sheltered from this wind and are therefore the driest. Atlantic currents, warmed by the Gulf Stream, bring mild winters, especially in the west, where winters are wet, especially over high ground. Summers are warmest in the south east of England, being closest to the European mainland, and coolest in the north. Snowfall can occur in winter and early spring, though it rarely settles to great depth away from high ground.

England accounts for just over half of the total area of the UK, covering 130410 km². Most of the country consists of lowland and mountainous terrain. Mountain chains are found in the north-west (the Cumbrian Mountains of the Lake District), north (the upland moors of the Pennines and limestone hills of the Peak District) and south-west (Exmoor and Dartmoor). Lower ranges include the limestone hills of the Isle of Purbeck, Cotswolds and Lincolnshire Wolds, and the chalk downs of the Southern England Chalk Formation. The main rivers and estuaries are the Thames, the Severn and the Humber Estuary. England's highest mountain is Scafell Pike, which is in the Lake District 978 m. England has a number of large towns and cities and, in terms of Larger Urban Zones, has six of the top 50 Zones in the European Union.

Scotland accounts for about a third of the total area of the UK, covering 78772 km². The faultline separates two distinctively different regions; namely the Highlands to the north and west and the lowlands to the south and east. The more rugged Highland region contains the majority of Scotland's mountainous terrain, including the highest peak, Ben Nevis, 1344 m. The Lowland areas, in the southern part of Scotland, are flatter and home to most of the population, especially the narrow waist of land between the Firth of Clyde and the Firth of Forth known as the Central Belt. Glasgow is the largest city in Scotland, although Edinburgh is the capital and political centre of the country. Scotland also has nearly eight hundred islands, mainly west and north of the mainland, notably the Hebrides, the Orkney Islands and the Shetland Islands.

Wales accounts for less than a tenth of the total area of the UK, covering 20758 km². Wales is mostly mountainous, though south Wales is less mountainous than north and mid Wales. The main population and industrial areas are in south Wales, consisting of the coastal cities of Cardiff, Swansea and Newport and the South Wales Valleys to their north. The highest mountains in Wales are in Snowdonia, and include Snowdon, which, at 1,085 m (3,560 ft) is the highest peak in Wales. The 14 (or possibly 15) Welsh mountains over 3,000 feet (914 m) high are known collectively as the Welsh 3000s. Wales borders England to the east and the sea in the other three directions: the Bristol Channel to the south, the Celtic Sea to the west, and the Irish Sea to the north. Wales has over 1,200 km (750 miles) of coastline. There are several islands off the Welsh mainland, the largest of which is Anglesey in the northwest.

Northern Ireland accounts for just 14160 km² and is mostly hilly. It includes Lough Neagh, 388 km², the largest body of water in the UK and Ireland. The highest peak is Slieve Donard 849 m in the province's Mourne Mountains.