In reply to chick mackay:
Hello,
I'm no Peruvian expert, but I know of some unclimbed peaks in the Andes.
We went to the Cordillera Carabaya in 2011. This is a small mountain range in S Peru. Although most of the major summits there have been climbed, there are still a few unclimbed summits. Most of the mountains have only been climbed once or twice by their easiest route, so there are plenty of new routes to go at.
The Carabaya is accessed from Macusani, a small town about a half a days drive north of Puno. It is further hours drive from the town to the nearest road to the mountains and from there a 3 hour walk up an idyllic valley to a flat grassy base camp. The weather is generally very stable and the temperatures are only a little bit colder than the Alps in summer. The mountains are around the 5000m+ mark.
It isn't a place to go if you looking for cutting edge alpine ascents, but is a great place to go if you are into exploration and fancy a bit of an adventure. I'd say it would be ideal for the young climber who had done a few big routes in the Alps and wanted to go somewhere more adventurous.
Be warmed though once you get there you are on your own. We went as two and it felt pretty committing. If I was going again I'd consider going as a team or 4 or 6. There is plenty to go at in the area and a team of 6 could get lots done over a three week period.
Here is a video that my partner made of the new route we did:
Drop me a PM if you want to know more. I've got a couple of expedition reports I can email you.
HTH
Tom