ApproachFollow the directions on the main page for Ingalls Peak, North Peak to reach the gully leading up to the notch between South (on left) and North Summits of Ingalls (the gully starts at Ingalls Lake below). As you're looking up the the gully, South Peak is above you and on the left; North Peak is above you and on the right (as is its South Ridge Route); East Peak is on the right but lower than North Peak. Your goal for the approach is a side gully directly below the notch separating the east ridge of North Peak from the East Peak. The low point near the right in this photo or the low point near the center of this photo (in both cases, East Peak is on right; North Peak is on left). East Ridge route climbs to that low notch and then traverses leftward staying on or near the ridge top to the North Summit.
Great overview photo: here.
Route DescriptionNelson and Potterfield guidebook (Vol. II) describes this route as being done in five pitches. As majority of the climbing here consists of 4th to low 5th class scrambling, most parties will no doubt do at least some simulclimbing. Where exactly you terminate the pitches is arbitrary (low angle terrain - endless belay station opportunities).
Pitch 1: low 5th, 200+ feet. Once you hike up the talus into the side gully mentioned above, look for low angle ramp system on the left side of the notch/chimney separating North Ingalls (its far east terminus) from East Ingalls Peaks. Rope up where you feel is comfortable. Climb the ramp system up. Terrain steepens slightly (from 4th class to low 5th class) about 40 feet before you top out on the ridge proper. Belay once atop the East Ridge.
Pitch 2: low 5th, c. 140 feet. Climb the easy terrain bypassing the mid-sized gendarme on its right. Continue hiking the ridge until you're forced tow downclimb ~20 feet (4th class) into a notch in the ridge. Belay in the notch.
Pitches 3-5: mostly low 5th with one section of 2 5.7 moves (supposedly), c. 500 feet. Describing these pitches on a pitch-by-pitch basis makes little sense as there's endless possibilities where you might choose to belay. Scramble out of the notch and follow the ridge staying atop the ridge and bypassing any difficulties on the right side. Midway through this section you'll encounter an easy, 20-foot long knife edge traverse (trending rightward, see photo) followed by more ridge line hiking. About 100 feet below (or rather before) the summit, you will come to the crux of the route (see photo): 2 moves of climbing rated at about 5.7 (crack on right and face features get you through this short section). Belay atop the summit of North Ingalls Peak.
Standard descent involves rapping the South Ridge route. From the summit scramble down (minimal exposure - most do this unroped) and left. In about 150-200 feet you'll come to the upper terminus of the South Ridge route and three very beefy rap bolts. Double 60 meter rope rap (double 50 meter might work too - untested) brings you to a large ledge at the base of the cracked slab (you're rapping the upper 2 pitches of South Ridge). Scramble straight down about 50 feet (class 3) and you'll see another rap set up (slings around boulder). Do another double rope rap to the hiking terrain in the notch between South and North Ingalls Peaks (top of above-mentioned gully). Hike down the gully passing the start of East Ridge on your left (easy to retrieve stuff from the base of the climb).