The DO area for red, rosé and white wines is located in the Spanish region of Madrid forms a semicircle around the southern suburbs of Madrid and is divided into three subzones. San Martín de Valdeiglesias lies to the west of the city, Navalcarnero borders Greater Madrid to the southwest and Arganda lies to the southeast. The area borders the two DO areas of Cebreros(Castile-León) and Méntrida(La Mancha). Together, these three DO areas form the Sierra de Gredos wine-growing area, which slopes down to the north towards the Alberche Valley and to the south towards the Tiétar Valley. At the time, the vineyards covered 60,000 hectares, but today there are only 11,800. Phylloxera arrived relatively late in the area in 1914 and caused devastating damage. This forced new plantings and was also used to grow better grape varieties, thus raising the quality standard. The continental climate is characterised by cold winters and warm to hot summers; rainfall ranges from only 460 mm (Arganda) to 650 mm (San Martin). White wines are produced from Airén, Albillo Real, Malvar (Lairén), Parellada, Torrontés (Alarije), Macabeo and Moscatel de Grano Menudo (Muscat Blanc ). The red and rosé wines are made from Garnacha Tinta, Tinto Fino (Tempranillo), Cabernet Sauvignon, Merlot and Syrah.