This approach description begins at the Gibson Creek Trailhead (which makes it longer than the Ducket TH) because we have actually been to and used the Gibson TH. The approach goes north on the Rainbow Trail for 6.2 miles before turning west up the South Brush Creek Trail for another 3.5 miles to a possible campsite. Because the Rainbow Trail crosses so many drainages, there is a lot of cumulative elevation gain and loss over that 6.2 miles resulting in an estimated 2,200 feet of unnecessary gain before reaching the S. Brush Creek Trail. If coming from the Ducket TH, we estimate 1,200 feet of unnecessary elevation gain and about 5 miles to the S. Brush Creek turnoff. Pick you poison.
From the Gibson Creek TH, head NNW on a lesser trail to gain the Rainbow Trail and continue north on the Rainbow through the numerous and tiring ups and downs. Turn west up the signed South Brush Creek trail (6.2 miles and up to 3 hours with packs) which works its way steadily up the valley. The trail intersection is signed and has a register. Hike through forest to the Goat Creek crossing (usually a trickle) and then climb more steeply a half mile up to a ridge, then drop down to South Brush Creek. You may have to search for a place to cross the creek, especially in higher runoff season. Regain the trail on the north side and head west up the valley. The trail will from this point on stay on the north side of the creek and usually a good distance from it. Our 1996 visit found the trail in good shape - not too rocky or worn. The middle section of this trail was the steepest and slowest. Hike/backpack to the last trees around timberline and look for a campsite as described in the Camping section.
At some of the last trees near timberline, at about 11,600 - 11,700 feet, we found a good campsite about 100 yards north of the creek, in a little "hollow" protected on 3 sides by trees and on the fourth side by the mountain slope. If it's windy, this is a somewhat protected location. Sorry - don't have GPS coordinates of the exact location. The location provided on the Google Earth photo is only a guess.
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