The W coast of Peru receives almost no rainfall, but the very persistent coastal fog (known as garúa) in winter results in humid conditions with drizzle precipitation at the seaward slopes of the coastal mountains, supporting fog oases with the so-called loma vegetation, a mixture of dispersed trees and shrubs, and small herbaceous plants. The Reserva Nacional de Lachay, established in 1977 in order to protect this type of ecosystem, is a popular leisure destination for people from Lima less than 100 km away.