You must go up through the red morraine starting at ski center (32 58.484S 69 21.506W). There are aproximately 5 or 6 km before you have to turn left (32 56.466S 69 23.596W). You will have San Bernardo and Mausy at your left all the time. After this, there is a gap at your left between Mausy and the Pico Parra ridge.
Turn left at the mentioned gap (32 56.466S 69 23.596W) and go up surrounding the ridge. Then turn right and you will see the summit at your right. At front you will see Morro Chato.
The red morraine is NW direction from the ski center. The second valley is SW of the morrine and then W. Summit (32 56.408S 69 24.000W) will be then at N. There are just a few steep sections when you left the red morraine. Having snow there is no problem with it, but with loose stone it can be hard to make. The rest of the climb is easy, but a long distance to cover (more than 7km from ski center).
An alternative route that is possible is to climb a section of stone wall after lefting the red morraine. It will left you in the summit ridge. It looks possible but technical gear will be needed to do it.
Depending on the amount of snow, crampons will be needed.
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