1hr east of Ensenada by bus
Petrohué is on the shore of Lago Todos Los Santos which stretches across towards Argentina. It´s very beautiful and there are some nice walks through the forest around the lake at the base of Volcan Osorno. The waterfalls 6km downstream are spectacular. The volume of water that rushes through the tiny chasms is amazing.
You can cross to Argentina through here, but the ferries and buses are run by a private monopoly providing an off-the-beaten-track guided tour in english. It´s pricy, and foreigners pay double. Off-the-beaten-track tourism is the new black.