Trekking in Puyehue National Park has still a low profile compared to the primary destinations like Mt. Fitzroy or Torres del Paine. Nonetheless the area is pretty popular with the locals so there's a decent infrastructure in place. Highlights of the trek include climbing the Puheyue volcano, a bizarre, barren volcanic high plateau and, last but not least, hot springs next to the camp where you can relax under the milky way. Providing a physical rating for the trek isn't easy because it depends heavily on the conditions. e.g. we did the trek fairly early in the season in December. Many portions of the volcano were still covered by a snow, lots of snow easily as deep as 5m in place. We literally had to scale snow walls in places and the progress was slow accordingly. It was fun but if you prefer an easier approach you should not start prior of January. Assuming dry conditions the trek is fairly easy with relatively good trek marks. Climbing the Puyehue volcano is strictly optional. It is usually no obstacle but fairly steep and strenuous. Most visitors probably prefer to arrive by car which can be securely parked on a Hacienda next to the trail head (for a little fee). You can also join commercial trips from/to Puerto Montt.