Mount Cleve Hill Honor Oak Rise The slightly lower central near-plateau is listed from the north: East Dulwich; Dulwich; Kingswood Estate with West Dulwich and West Norwood with Gipsy Hill. Two rises within this zone are Dawson's Rise and Knight's Hill. The second or western ridge is narrower and fractionally lower. It begins very broad and gradually in the south around Furzedown, Streatham then runs through central Streatham, Tulse Hill, Herne Hill, Denmark Hill/Champion Hill culminating at the crossroads of Dog Kennel Hill/Grove Hill/Champion Hill. Fourteen of its access points can be said to give areas of this rise their own 'Hill' or 'Mount' names:- Bedford Hill Mount Ephraim Road and Lane Streatham Hill Brixton Hill Upper Tulse Hill Tulse Hill Birkbeck Hill Herne Hill Red Post Hill Denmark Hill Champion Hill Dog Kennel Hill Grove Hill Bushey Hill Some of the above slopes are in the catchment of the Effra, which had widespread Victorian housing and commercial use so has been converted into parallel combined and surface water sewers which feed into the Crossness works and tributaries of the tidal Thames respectively. In the east the south slopes feed the Pool. To the south underlying layers of London Clay and Palaeocene between the ridge and the dip slope of the North Downs, where on the near side is the Graveney which feeds into the River Wandle. Human geography Political geography and landmark status The ridge and the historic oak tree known as The Vicars Oak (at the crossroads of the A212 Church Road and A214 Westow Hill) were used to mark parish boundaries. This has led to in particular the Crystal Palace area straddling the boundaries of five London Boroughs; Bromley, Croydon, Lambeth, Southwark and Lewisham. The area also straddles three postcode districts: , , and . The ancient boundary between Surrey and Kent passes through the area and from 1889 to 1965 the area lay on the south eastern boundary of the County of London. It included parts of Kent and Surrey until 1889 and then parts of Kent, London and Surrey between 1889 and 1965. For centuries the area was occupied by the Great North Wood, an extensive area of natural oak forest that formed a wilderness close to the southern edge of the then expanding city of London. The forest was a popular area for Londoners' recreation right up to the 19th century, when it began