From the Lawn Lake Trailhead hike up Lawn Lake Trail approximately 1.3 miles. Take a left onto Ypsilon Lake Trail and hike 3.2 miles to Ypsilon Lake. From Ypsilon Lake hike west up the climbers trail for approximately one mile. The climbers trail is well trodden and even has a couple of bridges built along its path. Once you break through tree line stay high along the north side of the valley as you contour through the boulders.
As you approach 12,000 feet examine the face to your right (north). This looks daunting, but is not nearly as difficult as it appears. Choose a line and head for the ridge. See this photo for one possibility. In the photo we chose to angle over as far as we could to the right so that we could attain the ridge as low as possible. Basically, anything between our path and the top of the ridge is class two. This face is crisscrossed with grassy ledges (invisible from below) that make the climbing much easier than it looks.
After gaining the ridge follow it to the summit of Ypsilon Mountain. The remainder of the hike is class 2, unless you try really hard to find a few short sections of class 3.
Why not the entire ridge?
This route is the one Gerry Roach describes in his Rocky Mountain National Park Guide. We followed this and after reaching the summit Nelson and I were a bit disappointed. It was just way too easy. We were hoping for some challenging class 3, but instead got almost entirely class 2.
Why didn’t Roach suggest climbing the entire ridge from the bottom at Spectacle Lakes? Nelson and I intended to find out. So for the descent we decided to downclimb the ridge. Instead of getting off where Roach suggested we decided to try to go down the ridge all the way to Spectacle Lakes.
We found out the hard way why Roach recommended what he recommended. From where we had reached the ridge earlier in the day it looked like there was more interesting scrambling farther down the ridge and the crux of the ridge might be getting around a large gendarme. About 100-150 yards past where we attained the ridge on the way up (see this photo) the ridge steepened dramatically. At first we were able to keep things class 3 by dropping down a little on the south side of the ridge and utilizing the grassy ledges. However, as the ridge steepened (and the south face steepened) the grassy ledges became fewer and more difficult to negotiate. The ridge proper was so steep that we could not see down it. By traversing down the south face we hoped to get around the steep part or at least see what it was like. By utilizing the ledge system we made it to within 40 vertical feet of the saddle between the ridge where we were and the gendarme, but could not proceed further.
We made the difficult decision to turn around and climbed back up the ledges to where we spied a gully leading down to the valley floor. The gully looked steep, but we didn’t really want to climb all the way up to where we attained the ridge in the morning so we gave it a shot. The gully got a little hairy towards the bottom but we made it to the valley floor.
We never got a good look at the crux of the climb. Really this photo and this photo are as good a look as we got at it. I still think it may be possible to climb the ridge all the way from Spectacle Lakes. However, it probably involves at least one short pitch of very serious class 4, or even 5, climbing.
I encourage somebody to try it. It looks like there are ways to bail down to the valley floor from the saddle between the gendarme and part of the ridge where we were forced to turn around (if it comes to that).
No essential gear is needed, just your standard kit for hiking in the mountains.