The northern Atacama Desert contains great mineral wealth, primarily copper and nitrates. The relatively small Central Valley, which includes Santiago, dominates the country in terms of population and agricultural resources. This area is also the historical center from which Chile expanded in the late 19th century, when it integrated the northern and southern regions. Southern Chile is rich in forests, grazing lands, and features a string of volcanoes and lakes. The southern coast is a labyrinth of fjords, inlets, canals, twisting peninsulas, and islands. The Andes Mountains are located on the eastern border.