Ypsilon Mountain at 13,514' is the fifth highest peak in RMNP and it's east face is one of the more imposing alpine features in the park.

Flanked by the Donner and Blitzen Ridges on either side of the dramatic Y Couloir, this east face of Ypsilon contains some of the most classic rock ridge and steep couloir climbs in Colorado.   Although these routes are known andsought after, they are rarely visited  due to the longer and more difficult approach involved in reaching this somewhat remote cirque on the east side of the park. 

In a Colorado MoJo article here, veteran mountain guide and ice guidebook author Jack Roberts, lists Ypsilon as one of his springtime favorite alpine climb.