South Rainbow Ridge
Summer Day Hikes
Distance: 5 miles round trip to pass from the highway
Elevation gain: 1800 feet
Trail type: Hiking
Considerations: Somewhat difficult to park at the highway
Rainbow Ridge provides one of the most spectacular, and intimidating sights for those driving the Richardson Highway through the Alaska Range between Delta and Glennallen. Unknown to most who admire it, the steep meadows, exposed ridge tops, and hidden cirques up there are accessible without technical mountaineering skills or the need to beat through thick walls of brush. This hike leads up a narrow canyon to a high pass with views of the remote far-eastern Alaska Range, and options for further exploration into the very high, austere summits and hidden cirques toward one of the summits of Rainbow Mountain itself.
From Delta, drive about 60 miles south on the Richardson Highway. The road winds along immediately below the scree fields and crags of Rainbow Ridge and makes a fairly sharp corner where it crosses a creek. There will be a small gravel road on the left, and then an even smaller trail leading across a broad ditch and then narrowly into the brush and trees. A high clearance vehicle you don’t mind scratching up can make it about 3/4 mile up this trail, where there is a small turnaround. Otherwise, pull into the gravel pit a little further down the highway and walk back to the trail.
In any case, the trail rises steadily along a creek and eventually comes to a section, after the vehicle turnaround, where it’s been washed out. It’s easy enough to proceed up the gravel and boulders along the creek. Following the creek and intermittent bits of trail, the pass is reached at about 2.3 miles. Be aware that this narrow creek canyon gets blasted by avalanches in winter, and the shaded piles of snow can take much of the summer to melt. Usually, it’s easy enough to walk on the dirty snow in summer, but the creek creates a tunnel through these piles and can make walking on top dangerous.
At a couple places, the steep canyon wall to the north relents enough that tundra vegetation reaches down to the creek. These make good spots to exit the canyon and hike steeply up into the high country. The first exit comes just before a side creek from the north. The hike up the meadow is very steep, but you’ll be amply rewarded by the view at the top of a minor summit, plus you’ll get to visit the mysterious green metal box that looks like it was placed there by aliens. If anybody has any idea what this is, I’d like to know. From the minor summit, it’s possible to drop down a bit to a minor pass, and then traverse north into a small alpine cirque under Rainbow Peak that’s hidden from the highway. Though I haven’t done it, it looks quite reasonable to scramble up the south summit of Rainbow from this direction as well.