The urban area covers about . It is located on mostly flat terrain in the Peruvian coastal plain, within the valleys of the Chillón, Rímac and Lurín rivers. The city slopes gently from the shores of the Pacific Ocean into valleys and mountain slopes located as high as  above sea level. Within the city are isolated hills that are not connected to the surrounding hill chains, such as El Agustino, San Cosme, El Pino, La Milla, Muleria and Pro hills. The San Cristobal hill in the Rímac District, which lies directly north of the downtown area, is the local extreme of an Andean hill outgrowth.