The route for Mt. Alice begins at the patrol cabin at Thunder Lake. There is a designated backcountry campsite there if you're lucky enough to get a permit. Otherwise, if backpacking in, you may have to stay back at the Siskin or North St. Vrain campsites. At the cabin, you may want to pause for several pictures of the lake, cabin and abundant wildflowers. Begin hiking west from the cabin on a trail that follows along the north shore of the lake and cross the northern of the two feeder streams into the lake. If you're a camera bug, you'll still be snapping numerous pictures. The easy-to-follow trail will lead around the north shore and westward into the forest and up towards the “Boulder-Grand Pass.” You can follow this unmarked trail all the way up to “Lake of Many Winds,” (a very appropriate name). As we stood at this small lake, winds assailed us from above and caused some concern for what we might encounter once on the ridge above. Clouds swirled around the sheer cliffs of Tanima Peak
From the lake, it is a steep ascent on tundra, rock and scree to the "Boulder-Grand Pass" with a good 500 feet of stiff gain. We found it windy at the saddle, but once we headed north along the ridge, it wasn’t quite so bad. From the pass/saddle, it's about 1.25 miles to the summit of Mt. Alice by just following the ridge. The hiking is mostly easy across rock embedded tundra. The last few hundred feet to the summit is on larger boulders. Continue to the eastern most of the two summits, but you may want to tag the western summit for good measure. If weather permits you can see over to Chiefs Head, Pagoda and McHenry’s.
For our return route, we decided to go a different way rather than retrace our route back. If you use this descent route, the Class rating will go to 2+. We headed back down the south ridge of the peak, but after a short distance, veered southeast and descended a moderately steep slope of loose rock and tundra. For a while, we followed a broad ridge that descends east into the large basin east and south of the peak, but then we dropped off the north side and into a rocky basin. Here, we encountered huge boulders that consumed a lot of time to cross over. We paused a few times to admire and photograph the 1,200 foot sheer, east face of Mt. Alice. This expanse of rock looks every bit as challenging as the Diamond on Longs Peak. After much tedious boulder hopping and clambering, we eventually cleared this hazard and began a descent down the main drainage for this basin. The route we followed led us into a forest that was not too hard to negotiate. We were a little off on our expectation of exactly where we would come out. We thought we would emerge out of the forest directly north of Thunder Lake, but actually found ourselves on the Thunder Lake trail, east of the cabin and well on to beginning it’s descent down the valley. The boulder talus made this way down less than thrilling. Also, earlier in the season, you may encounter snow so ice axe could be handy. This descent route does have the merit of giving you a close up view of the impressive east face.
Links to other information, routes & trip reports for this peak that may be helpful.