Mile Oak is on the edge of the South Downs and as such has much farmland nearby; the Monarch's Way and Sussex Border Path long-distance footpaths skirt the edge of the built-up area. The first urban development occurred in the 1930s, and growth continued throughout the postwar era; houses were provided by the council, private builders and housing associations, many of them provided for people occupying substandard houses in the southern part of Portslade.