Because distances are great, public transportation is limited, and roads are few and slow, Aisén [1] justifies a rental car, preferably with high clearance. Vehicles are also few, so rental reservations are advisable for visitors flying into Balmaceda/Coyhaique, which is roughly the midway point on the Carretera Austral.
Coyhaique [2] is the best base for excursions north and south, and to Laguna San Rafael by catamaran or air taxi. Northbound on the Carretera Austral, it takes at least a week or 10 days to see roadside or near-roadside highlights like Parque Nacional Queulat [3], the Puyuhuapi hot springs [4], Parque Natural Pumalín [5], and the Río Futaleufú [6]’s world-class white-water.
Southbound on the highway, it needs at least a week to enjoy Cerro Castillo [7], Lago General Carrera, the singular fishing village of Caleta Tortel [8], and the wild end-of-the-road scenery at Villa O’Higgins [9].
For visitors heading south from Puerto Montt [10], with rental cars, ferry reservations are advisable, especially for the January–February-only service between Hornopirén [11] and Caleta Gonzalo.
Links:
[1] http://www.moon.com/destinations/chile/northern-patagonia/aisen-and-continental-chiloe
[2] http://www.moon.com/destinations/chile/northern-patagonia/coyhaique
[3] http://www.moon.com/destinations/chile/northern-patagonia/-northern-carretera-austral/parque-nacional-queulat
[4] http://www.moon.com/destinations/chile/northern-patagonia/-northern-carretera-austral/termas-de-puyuhuapi
[5] http://www.moon.com/destinations/chile/northern-patagonia/-northern-carretera-austral/parque-natural-pumalin
[6] http://www.moon.com/destinations/chile/northern-patagonia/-northern-carretera-austral/futaleufu
[7] http://www.moon.com/destinations/chile/northern-patagonia/-southern-carretera-austral/villa-cerro-castillo
[8] http://www.moon.com/destinations/chile/northern-patagonia/-southern-carretera-austral/caleta-tortel
[9] http://www.moon.com/destinations/chile/northern-patagonia/-southern-carretera-austral/villa-o-higgins
[10] http://www.moon.com/destinations/chile/sur-chico/puerto-montt
[11] http://www.moon.com/destinations/chile/sur-chico/puerto-montt/sights/hornopiren-rio-negro