via Wallasey Pool (Birkenhead Docks). Further south, the Clatter Brook and Dibbinsdale Brook drain into the Mersey at Bromborough Pool. Two approximately parallel sandstone ridges run down the length of the peninsula. The western ridge is made up of Grange and Caldy Hills at 256 feet in height, then Thurstaston Hill (298 ft), Poll Hill in Heswall (350 ft, the highest point on the Wirral) and Burton (222 ft). The less continuous eastern ridge consists of Bidston Hill (231 ft), Prenton (259 ft) and Storeton Hill (229 ft). The shallow Fender valley runs between these ridges. Climate The Wirral features a temperate maritime climate (Köppen: Cfb) with mild summers, cool winters and rainfall spread evenly throughout the year. A weather station was maintained on the peninsula, at Bidston, between 1845 and 2002. Human geography The major urban centres of the Wirral are to its east: these include Birkenhead and Wallasey. To the west and south, the Wirral is more rural. Two-thirds of the population of the Wirral live on one third of the land in Birkenhead and Wallasey, according to Wirral Metropolitan Borough Council. Other towns to the south and west of this area are usually considered part of the Wirral: notably, Ellesmere Port is often described as one of its "border towns". For regional economic planning, the Metropolitan Borough of Wirral is considered part of the Liverpool City Region. Settlements There are many towns and villages on the Wirral. Those administered by the Metropolitan Borough of Wirral are listed in List of towns and villages in Wirral (borough). Those also on the Wirral but administered by Cheshire West and Chester include: M53 Divide The M53 is also seen as an east–west divide between the affluent and developing areas of the Wirral. Landmarks Despite containing urban and industrial areas, the Wirral still has picturesque villages, sandy beaches, large areas of land owned by the National Trust as well as views across the two estuaries and out into the Irish Sea. Among the areas of open land are Bidston Hill, Caldy Hill, Eastham Country Park, including the Victorian Pleasure Gardens, Hilbre Island, North Wirral Coastal Park, Thurstaston Common and Thor's Stone and the Wirral Way. Ness Botanical Gardens are part of the University of Liverpool and have won many awards. The visitor centre at RSPB Burton Mere Wetlands provides birdwatching facilities in the Dee Estuary nature reserve. Places of architectural interest