Throughout much of their length the Andes rise close to the Pacific coast and descend abruptly to low plains on the east. As the main watershed of the continent, the system is the source of short streams flowing to the Pacific and also of most of the headstreams of South American rivers flowing east and north. It is a formidable barrier to transportation. The only railroad crossings are those connecting Chile with neighboring Argentina and Bolivia. The Andes are rich in nonferrous metals but have no coal.
Many deposits are inaccessible.
The chief minerals obtained are gold, silver, copper, tin, platinum, antimony, lead, zinc, bismuth, and vanadium. The natural pastures of the central plateau are suitable for cattle raising. Colombia exports cattle, and Peru has milk-canning and livestock industries. Sheep, goat, llama, and alpaca raising are widespread in Peru and Bolivia. Both countries export sheep and alpaca wool.