The hike up to the top of Arco Iris is the jewel in the crown of the Cochamo Valley, one of the best walks in Patagonia and therefore in the world. You’ll need strong legs and if you’re not sure if you can do it you probably can’t. You will get most of the views of the valley and alerce trees just by going up to the first mirador. If you want to be able to see the sea, volcanoes and the valley at the same time you’ll need to get in training to withstand a long, long day. The whole route is 13km with 1,300m of uphill and downhill.
The first mirador is a little easier and should be accessible by anyone used to hiking, coming in at a mere 6.5km round trip and 850m of ascent and descent.