Peru is divided into three main regions, Coastal, Sierra (Mountain), and Selva (Jungle/ forest). 65% of Peru is Selva (jungle/ forest), 20% is Sierra (mountain), and 15% is coastal. The forest is a part of the Amazon rain forest with the source of the Amazon river starting in peru. The mountains are mostly part of the Andes mountain range. The coastal area is largely desert like. This is due to a number of factors ranging from the cold ocean currents, to other climatic conditions.