South of Chillán and the Itata Valley, Chile is intersected by the great Río Bío Bío, generally considered the southern limit of the Central Valley. One of Chile’s longest rivers, it cuts a 380km diagonal slash across the country, emptying into the ocean by the coastal city of Concepción, over 200km north of its source in the Andean mountains. For more than three hundred years the Bío Bío was simply “La Frontera”, forming the border beyond which Spanish colonization was unable to spread, fiercely repulsed by the native Mapuche population.
Today, the Bío Bío Valley, which stretches 400km southwest from the mouth of the Río Bío Bío, still feels like a border zone between the gentle pastures and meadows of central Chile, and the lakes and volcanoes of the south. While the valley floor is still covered in the characteristic blanket of cultivation, dotted with typical Central Valley towns such as Los Angeles and Angol, the landscape on either side is clearly different. To the west, the coastal range – little more than gentle hills further north – takes on the abrupt outlines of real mountains, densely covered with the commercial pine forests’ neat rows of trees and, further south, there are hints of the dramatic scenery to come in the Lake District, with native araucaria trees in their hundreds within Parque Nacional Nahuelbuta.
Cut off by these mountains, the towns strung down the coast road south of Concepción – such as Lota, Arauco, Lebu and Cañete – feel like isolated outposts. To the east, the Andes take on a different appearance, too: wetter and greener, with several outstandingly beautiful wilderness areas like Parque Nacional Laguna del Laja and Parque Nacional Tolhuaca.