This route description starts from the top of Mt. Bierstadt. To get there, start at the Guanella Pass Trailhead and climb the standard route. The hike to the summit will probably take you between 2 and 3 hours depending on your fitness level. The standard route is a class 1 walk-up all the way.
From the top of Mt. Bierstadt descend north toward The Sawtooth. Don't climb down the ridge of The Sawtooth, stick to the east face. When you've lost most of the elevation to get down to the lowest part of The Sawtooth then head over to the ridge. While you're losing elevation, the cairns are hard to follow, but when you actually get to the ridge the trail is well marked by cairns.
The first half of The Sawtooth is what I would consider a class two scramble--no exposure, just using your hands often. At about halfway across The Sawtooth, there is some more serious climbing. You have to climb up and over a couple of large rocks that requires using hand and foot holds etc. Check out the photo submitted by peakwolf for a great shot of the east face of The Sawtooth.
At about 3/4 of the way across The Sawtooth, the cairns lead you across from the east face to the west face. This is where the exposure begins and the portion that I would consider class three—lots of exposure, steep climb, loose scree and dirt slope. The east face has a nice gradual slope to it, the west face on the other hand is a pretty shear drop for several hundred feet. The narrow trail continues to lead to the final pitch. The final pitch (less than 200 yards) was a little scary: a steep climb up very loose scree and dirt slope with a good deal of exposure.
After completing this final pitch, you’re off The Sawtooth. You can climb up to the cliff at the north end of The Sawtooth, or just begin the descent back to the trailhead. (Mount Evans and Mount Spalding are also relativley close by and many people choose to climb those at the same time.) The slope that you climbed off The Sawtooth onto slopes gently downward to northwest. Walk down this slope until you hit the gully. You can’t miss the gully because after you pass it the slope begins to slope upward. Follow this gully all the way down to the beaver ponds. There are no cairns to lead the way, but previous hikers and animals (most likely mountain goats) have worn a trail through the scree and grass.
When you get to the beaver ponds, do your best to follow the trails through the willows. Depending on how wet the ground is, you might have the best luck staying close to the beaver ponds. If the ground is real swampy, you will probably want to climb a little up the slope on the south side of the beaver ponds. If you stay below the stand of trees on the hillside and curve around to the south you’ll eventually meet up with the trail.
When I did this hike it took me two hours and twenty minutes to hike from the trailhead up the conventional trail to the summit of Mount Bierstadt. It took me five hours to get down via The Sawtooth and gully.
Check out my website for a complete set of my Mount Bierstadt photos: www.leachfam.com.
I did this hike in September and needed no special equipment, just standard gear for hiking in the mountains. If you were going to do this hike in the early spring or winter I'd expect you'd need all kinds of gear: ice axe, crampons, snow shoes, ropes, etc.