No motorized vehicles or bicycles within the Mount Zirkel Wilderness.
A great hike up to the spectacular Rainbow Lake. The hike will be considered moderate to easy by seasoned hikers, but is a nice challenge for flat landers from out of state.
Need to Know
No access fee. The trailhead is located at the end of County Road 22A. The dirt road well maintained. There is parking for 10-12 cars. There are no restrooms or potable water source.
The hike to Rainbow Lake follows a portion of Rainbow Lake Trail #1130, which runs from the Rainbow Lake trailhead to its terminus with the Wyoming Trail #1101 (Continental Divide Trail). From the trailhead, the trail starts through a mixed forest with moderate to severe lodgepole pine beetle kill. Many of these trees have been cut down. The trail is wide enough for ATV's at this point.
The trail will cross the Grizzly Helena Trail #1126 and enter the Mount Zirkel Wilderness. At this point, the trail will narrow into well-maintained singletrack following a ridgeline. The views get better and better as the trail steadily gains elevation. The iconic rock formation Rabbit Ears will be visible in the distance to the south. The other interesting thing to notice is that almost all the trees to the south are aspen and all the trees to the north are conifers. The trail almost perfectly splits the two.
About two miles in the trail will leave the ridge and run along the northern slope of the ridge. You'll come across a stream crossing that is easy to navigate (at least in August). Lower and Middle Rainbow Lake will be to your right but you'll not see them. At roughly three miles in the trail will flatten out and Rainbow Lake will come into view. The trail skirts the lake to the south and you'll have to leave the trail in order the explore the lake. Norris Creek between Rainbow and Middle Rainbow Lake is really pretty with a waterfall. The views are fantastic with snow on the peaks in the distance. The lake valley can be quite breezy.
Rainbow Lake is a fantastic place for lunch and a quick rest before heading back.
History & Background
Rainbow Lake lies within the Mount Zirkel Wilderness. The wilderness area was created in 1964 and is 160,000 acres in size.