The town is bisected in two in terms of soil: the north of the town is on gravel and sand deposited around the London Clay of most of London as the Thanet Formation, whereas the south-east of the town is on uneroded chalk slopes: Epsom Downs refers to these slopes reaching up to wide plateau (on which sit the formerly water-scarce settlements: Box Hill, Walton on the Hill, Tadworth and Kingswood, Surrey) and covers 990 acres of what is in traditional terms and in technical terms, part of the area of the settlement, called Epsom Downs.