The heartland, which coincides partly with the counties Powys, Denbighshire, and Gwynedd, extends from the Brecon Beacons in the south to Snowdonia in the north and includes the two national parks based on those mountain areas.
To the north and northwest lie the coastal lowlands, together with the Lleyn Peninsula (Penrhyn Llŷn) in Gwynedd and the island of Anglesey.
There is no markedly wet or dry season; roughly 4 inches (88 mm) of precipitation are recorded in April, whereas 6 inches (142 mm) are typical in January.
Wales has a maritime climate dominated by highly unpredictable shifts in Atlantic air masses, which, combined with the diverse range of elevations, often cause local conditions to vary considerably from day to day.Precipitation is frequent and often more than adequate, with annual totals averaging 55 inches (1,385 mm) for the country as a whole.Among the lesser rivers and estuaries are the Clwyd and Conwy in the northeast, the Tywi in the south, and the Rheidol in the west, draining into Cardigan Bay (Bae Ceredigion).The country’s natural lakes are limited in area and almost entirely glacial in origin.Anglesey (Môn), the largest island in England and Wales, lies off the northwestern coast and is linked to the mainland by road and rail bridges.
The varied coastline of Wales measures about 600 miles (970 km).Famed for its strikingly rugged landscape, the small nation of Wales—which comprises six distinctive regions—was one of Celtic Europe’s most prominent political and cultural centres, and it retains aspects of culture that are markedly different from those of its English neighbours.Giraldus Cambrensis (Gerald of Wales) had topography, history, and current events alike in mind when he observed that Wales is a “country very strongly defended by high mountains, deep valleys, extensive woods, rivers, and marshes; insomuch that from the time the Saxons took possession of the island the remnants of the Britons, retiring into these regions, could never be entirely subdued either by the English or by the Normans.” In time, however, Wales was in fact subdued and, by the Act of Union of 1536, formally joined to the kingdom of England.Other plateaus give way to coastal flats that are estuarine in origin.Wales consists of six traditional regions—the rugged central heartland, the North Wales lowlands and Isle of Anglesey county, the Cardigan coast (Ceredigion county), the southwestern lowlands, industrial South Wales, and the Welsh borderland.The Severn and Wye, two of Britain’s longest rivers, lie partly within central and eastern Wales and drain into the Bristol Channel via the Severn estuary.