Since it so seldom rains, the key to Elqui Valley's lushness is irrigation.  This dam is located about 15 minutes west of the house, on the way to La Serena, and it provides the lifeblood to the Chilean grapes and other world-class produce you find in every U.S. supermarket.  The grapes are also used to produce a famed brandy called "pisco"; be sure to sample the various local varieties, whether on your own or as part of a distillery tour.