Or, why the PCT climbs up into the Laguna Mountains: http://www.latimes.com/news/printedition/la-000093536nov23.story which explains why the border patrol's trail signs have those seemingly incongruous pictures of death by dehydration and also death by drowning, e.g. http://www.oakapple.net/pcnst/past/photo/sc-pct/a/01-04-27-a03/p4270052.jpg