The main obstacle in making a ridge traverse between Snowdon and UN13,046 (N 2/South Snowden) consists of three notches along the connecting ridge. When we attempted this, we had no information regarding the difficulty of these notches, so the route that follows avoids the first notch and involves a significant loss in elevation that some may wish to avoid. Additionally, this summit is climbed in sequence with Snowdon Peak, so the mileage and elevation gain estimates are measured from the Snowdon summit. It's one mile by our route between the two peaks and from N 2, it's another 3.0 miles to return to the TH.
From the relatively flat and rocky summit of Snowdon Peak, enjoy a brief stroll SW, heading for where the ridge narrows up. From a vantage point near the Snowdon summit, you can distinguish three notches in the ridge that could pose significant problems. What follows next is our written account of dealing with the notch problems:
We headed SW from the summit and followed the ridge to the first notch, (involved some Class 2+ down climbing) which was divided by two large couloirs. We crossed to the head of the second couloir and did not like what we saw and went back to the head of the first. At that second, lower couloir, we tried to descend on the east side of the ridge but encountered a short ledge that we felt was too risky to descend without some kind of protection, of which we had none and the rock was wet. While trying to decide what to do, another couple came along and we explained to them what we were finding. They were following some instructions in a guidebook we did not have that WAS FOR A CIRCUIT OF Snowdon Peak only. The guidebook instructed to descend west down one of the couloirs, which they proceeded to do. It was very steep, full of loose rock, but still manageable. We later on learned that you could descend about 600 feet down this way, then begin a traverse below the ridge on the west side toward UN13,046.
As for us, from the first couloir, we headed east and down a little and spotted something of a descending ramp that cut down and across the south face of Snowdon for several hundred feet. For the most part, the ramp was a grassy bench, never very wide, but easy to negotiate for quite a ways. Then it narrowed into a diagonal couloir filled with more outstanding columbine and led us to the head of a talus slope that we could descend south into the large basin between the two summits. We had descended to about 12,200 feet. Then, walking on mostly grassy terrain, we began contouring across the basin and next headed for a talus slope, cutting through some rock outcrops that led back up to the last notch in the main connecting ridge, just north of UN 13,046.
We continued hiking up the steep, loose, broken and now slick rock (because of rain) and boulders to the final notch. If coming along the ridge from Snowdon, we determined this notch to be a substantial obstacle along the ridge that would have been difficult to navigate. We felt it was definitely best that we had not continued along the ridge. From the head of the notch, it was an easy final walk to the summit. We arrived there about 2 hours after leaving Snowdon, delayed because of time consumed looking for the best route over.
Enjoy the expansive summit view. This peak sits almost directly west of the Grenadiers. Mount Garfield is clearly visible directly east across the valley and beyond it, you can spot the summits of Electric, Graystone, Arrow and Vestal.
To return to Andrews Lake, hike back down to the notch and then drop to the west down rocky slopes to a pleasant grassy area, dotted with small tarns and potentially nice campsites. Hike to the east side of the 12,450 foot outcrop and begin dropping north toward the meadow-filled basin from which you began your day. Pass another small tarn at 12,000 feet tucked away into a sheltered area and descend along grassy benches broken by small cliffs. This requires a little route finding but eventually will get you down. In the meadows below, regain the trail from the morning and follow it back to the Crater Lake trail and then back down to Andrews Lake.
Links to other information, routes & trip reports for this peak that may be helpful.