Wales is a country that is part of the United Kingdom. It is bordered by the Irish Sea to the north and west, England to the east, the Bristol Channel to the south, and the Celtic Sea to the south-west. As of the 2021 census, it had a population of 3,107,494. It has a total area of 21,218 square kilometres (8,192 sq mi) and over 2,700 kilometres (1,680 mi) of coastline. It is largely mountainous with its higher peaks in the north and central areas, including Snowdon, its highest summit. The country lies within the north temperate zone and has a changeable, maritime climate. The capital and largest city is Cardiff.