Rasac is a long, relatively squat mountain on the western edge of the Huayhuash, across the glacier from the tallest peak in the range, Yerupaja. Although it´s a 6,017 meter mountain, Rasac´s broad profile is dwarfed by the elegant peak behind it. Rasac means Toad.
Rasac is considered to be the easiest 6,000 meter peak in the range, which is to say it´s not all that easy at all. The long, snowy West Face is divided by a series of buttress, most of which have routes in the D-range. The Right Buttress is unclimbed. The East Face is almost all rock, most of which seems to be crappy. There is allegedly a AD snow route up a gulley on this face that looked in the summer of 2007 to be totally out of condition.
The Normal Route (which Jeremy Frimmer says has at least 25 documented ascents, making it the closest thing to a trade route in the range) is the SE Ridge, which was first climbed solo by Schneider in 1936, the second ascent in the Huayhuash. The nominal rating is AD. Take this with a grain of salt.
Getting ThereApproach as for the Huayhuash trek. Day One reach Laguna Jauacocha and pass to the far side of the lake to avoid the hordes of trekkers. From Laguna Jauacocha you can hike up to either the West or East faces (the latter for the SE Ridge).
For the West side, Frimmer´s book suggests following the Alpine Circuit to gain the upper Rasac Valley and then the Rasac Glacier. Details about how to do this are vague.
For the East side, it´s a long slog up to Moraine Camp at 4,800 meters, about five hard hours. From Jauacocha follow the faint trail to Laguna Solterachocha and then an even fainter climber´s trail on an exposed hillside with lots of bushwhacking. Cross a boulder field to gain a moraine and follow cairns up to the crest around 4,800 meters.
Mules will go about half an hour up the valley (circa 4,200 meters) on Day Two. From here you´ll have to ferry loads to your camp.
There are several camp sites up here, close to water. Another three hours or so up the moraine will take you onto the flat Yerupaja West Glacier and up to the Seria Norte-Rasac col (5750). A high camp on the glacier is possible but it´s probably a better idea to make it a long day from Moraine Camp.