Very nice hike to get to about 4500m elevation. Leave road at one point and follow trail up the valley. Carlos (age 90) has lived there all his life tending his sheep and llamas. His dogs will run up barking when you are about 500 m from his place. It is best if you wait or advance only when they run back until Carlos appears. He is delightful but a little forgetful. He expects 2 Soles per person to pass through his land and on up to the lake. He does maintain trail and pick up the litter left by the inconsiderate. He also likes canned tuna so consider bringing a few cans up for him.