ApproachThe closest trailhead is at the end of the Onion Valley Rd on the east side of Kearsarge Pass. Take the Kearsarge Pass Trail to Charlotte Lake and follow the PCT over Glen Pass. At Rae Lakes, turn left at the trail junction to Sixty Lakes Basin. Where the trail turns north just east of Mt. Cotter, leave the trail and head SW towards Sixty Lakes Col. This is the low point of the ridge south of Mt. Cotter, and provides class 2 access to Gardiner Basin. Climb down the west side of the col and head west towards Mt. Gardiner.
Bob Pickering offers another approach route, shorter but more cross-country:
Hike over Kearsarge Pass and turn north on the JMT shortly before Charlotte Lake. When the JMT turns right at about 11,100 feet, head NW across an obvious bowl. Climb out of the bowl and continue NW to "Charlotte Col" at the south end of Sixty Lakes Basin. Drop down about 300 feet into the basin using the chute just west of the low point. There is much loose rock on this descent. Traverse directly to Sixty Lakes Col without losing or gaining elevation. This traverse has surprisingly decent rock. Climb down into Gardiner Basin and head for Mt. Gardiner. This approach saves considerable mileage and elevation gain over following the JMT all the way to Rae Lakes before reaching Sixty Lakes Basin. The cross-country travel is strenuous, so not everyone will prefer this route to the trail.
Route DescriptionThis is not a difficult route, and there are no tricks to route-finding. It is class 2 all the way to the south summit, and the class 3-4 starts there in traversing to the north summit. Secor refers to this as the "Northeast Chute" but there is little "north" about it.
From the upper reaches of Gardiner Lake, head west up the obvious chute. Halfway up it widens considerably and is more of a large bowl than a chute. Climb this directly to the south summit. There is some permanent snow on this route that can be easily bypassed by mid-summer. Earlier in the season it may be advisable to carry axe and crampons.
For the class 4 traverse from the south to north summit, see the Route Description for the South Slope Route.
This route can be used to gain access to Gardiner Basin from Charlotte Creek, by first climbing the South Slope before descending the East Chute.