action of longshore drift. The town has been forced into making artificial breakwaters to keep the port in being. These breakwaters have been extended and adapted so that the port lies almost entirely on reclaimed land. The higher land on either side of the valley – the Western Heights and the eastern high point on which Dover Castle stands – has been adapted to perform the function of protection against invaders. The town has gradually extended up the river valley, encompassing several villages in doing so. Little growth is possible along the coast, since the cliffs are on the sea's edge. The railway, being tunnelled and embanked, skirts the foot of the cliffs. Dover has an oceanic climate (Köppen classification Cfb) similar to the rest of the United Kingdom with mild temperatures year-round and a light amount of rainfall each month. The warmest recorded temperature was , recorded at Langdon Bay on 25 July 2019, Whilst the lowest recorded temperature was , recorded at Dover RMS on 31 January 1972. The temperature is usually between and . Demography In 1800, the year before Britain's first national census, Edward Hasted (1732–1812) reported that the town had a population of almost 10,000 people. At the 2001 census, the town of Dover had 28,156 inhabitants, while the population of the whole urban area of Dover, as calculated by the Office for National Statistics, was 39,078 inhabitants. With the expansion of Dover, many of the outlying ancient villages have been incorporated into the town. Originally the parishes of Dover St. Mary's and Dover St. James, since 1836 Buckland and Charlton have become part Dover, and Maxton (a hamlet to the west), River, Kearsney, Temple Ewell, and Whitfield, all to the north of the town centre, are within its conurbation. Economy Retail The town's main shopping streets are the High Street, Biggin Street, Market Square, Cannon Street, Pencester Road and Castle Street. The Castleton Retail Park is to the north-west of the town centre. The new St James' Retail and Leisure Park opened in 2018 and is a southern extension of the town centre and consists of shops, restaurants, a Travelodge Hotel and a Cineworld Cinema. Shipping The Dover Harbour Board is the responsible authority for the running of the Port of Dover. The English Channel, here at its narrowest point in the Straits of Dover, is the busiest shipping lane in the world. Ferries