Flattop Mountain Hallett Peak
excerpts from the book
Incredible Backcountry Trails 
by David Day

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Incredible Backcountry Trails
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    Distance: 9.4 miles (round trip)

    Walking time: 7 hours
    : 3,275 ft. gain/loss
      Bear Lake Trailhead (start): 9,480 ft.
      Flattop Mountain: 12,324 ft.
      Hallett Peak: 12,713 ft.

    Trail: Good trail as far as Flattop Mountain, but there is no developed trail for the last 0.4 miles up Hallett Peak. Some miner scrambling is necessary.

    Season: Midsummer through mid-fall. There is usually snow on the trail from mid-November through mid-July.

    Vicinity: Rocky Mountain National Park, near Estes Park

    Flattop MountainAndrews Glacier


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    This hike will take you to the top of two well known peaks on the Continental Divide in the center of Rocky Mountain National Park. The two peaks rise majestically above Bear, Dream, and Emerald Lakes, and are constantly photographed by hikers walking through the Tyndall Gorge to those lakes. (See photograph page 104). Hallett Peak has a particularly distinctive shape, and few who have seen it from below do not relish the thought of climbing to its summit. The cliffs facing the Tyndall Gorge on its eastern side present a difficult technical challenge, but the trail described here approaches the summit of Hallett Peak from the relatively easy western side.

    Begin by walking north from the Bear Lake Trailhead along the eastern shore of Bear Lake. As you walk, pause to look west at your destination: Hallett Peak on the left flanked by Flattop Mountain on its right. Within 200 yards you will come to a trail junction where a sign directs you to the right along the path to Flattop Mountain. From that junction the trail begins climbing north through a picturesque field of granite boulders towards the Bierstadt Lake Trail junction 0.3 mile later. There you must bear left. Finally, 0.8 mile after leaving the trailhead you will come to the third well-marked junction where the trail to Flattop Mountain departs on the left.

    After leaving the third trail junction the path begins climbing up a moderate but unrelenting grade that persists for the next 3.3 miles, all the way to the summit of Flattop Mountain. The climb is long, but there are several diversions along the way. After 0.7 mile you will arrive at a gorgeous overlook point that lies directly above Dream Lake. The shimmering lake is 500 feet below the trail at this point, and five miles to the south you can see the distinctive shape of Longs Peak, the parks only fourteener, silhouette prominently on the skyline.

    1.1 miles beyond the Dream Lake Overlook, at about the point where the trail crosses the tree line, you will come to a second overlook point above Emerald Lake. The lake lies directly below the overlook, 1,200 feet down in the bottom of the Tyndall Gorge. Distant views of the surrounding mountains also open up as you leave the forest behind. Bierstadt Lake is particularly obvious-a small, round, isolated lake 2.6 miles to the northeast on a bench above Glacier Basin.

    0.3 mile before reaching the summit of Flattop Mountain the trail approaches the rim of the Tyndall Gorge, from where you can see the Tyndall Glacier below you and Hallett Peak on the opposite side of the canyon. From there it is an easy 10-minute walk the rest of the way up Flattop. The mountain is well named. It is so flat on top that you will scarcely be able to tell where the actual summit is. The land all along the west side of the Continental Divide is relatively flat in this area, rising gently from the west only to drop precipitously on the other side of the Divide. It is interesting to note that this pattern is repeated frequently throughout the West’s north/south mountain ranges. It is also a feature of the Sierra Nevada Range in California.

    In order to climb Hallett Peak you must walk south from Flattop, circumscribing the rim of Tyndall Gorge, and then turn east up the western slope of Hallett. There is no developed trail along this portion of the hike, but the route is easy. From the saddle between Flattop and Hallett you must gain 400 feet to reach the second summit. Many landmarks of Rocky Mountain National Park can be seen from the top of Hallett Peak. Grand, Granby, and Shadow Mountain Lakes are clearly visible on the west side of the Continental Divide, as are many of the lakes on the east side of the Divide.

    Andrews Glacier

    Most people return from Hallett Peak the same way they came, but for the adventurous there is another alternative: returning by way of Andrews Glacier. This choice will add 0.9 mile and about 45 minutes onto the total length of this hike. Andrews Glacier, located 1.2 miles south of Hallett Peak, offers a feasible route for descending from the crest of the Continental Divide down to Loch Vale where there is a good trail back to the Bear Lake Road. When conditions are right the descent down the face of the glacier is easy, but there is some danger and caution is advised.

    The best time of year to do the Hallett Peak/Andrews Glacier hike is midsummer, when the snow on the trails has melted but there is still plenty of snow covering the glacier. By late August conditions on the glacier are no longer ideal. Water running under the snow can form hidden snow bridges, especially on the edges of the glacier, and serious injuries have been incurred by people falling through these bridges. Also, a period of warm weather followed by a freezing night will inevitably cause a layer of ice to form over the glacier making a safe descent all the more difficult. If you loose your footing and go into an uncontrollable slide down the glacier you run the risk of either slamming into an exposed boulder or sliding into the freezing water of Andrews Tarn at the bottom of the glacier.

    Getting from Hallett Peak to the top of Andrews Glacier will take you about 45 minutes. First you must descend 400 feet along the crest of the Divide to the top of Chaos Canyon. This canyon also has a glacier at its head, but the Chaos Glacier is much too steep and unstable for a safe descent. Nevertheless it is worth pausing to enjoy the view down the Canyon. Lake Haiyaha is clearly visible in the bottom of the gorge from this viewpoint. From Chaos Canyon it is another 0.7 mile to the top of Andrews Glacier. There is no trail between Hallett Peak and Andrews Glacier, but, again, the route is not difficult.

    When descending the glacier pick the path that is the least steep and do not go too close to the edges. The total elevation loss is about 550 feet over a horizontal distance of 0.3 mile. The average angle of descent is only about 20 degrees, so if the surface is not icy it is not difficult to arrest a slide. But if the surface of the glacier is icy the situation can be much different. In that case do not attempt a descent unless you have an ice axe and know how to use it!

    As you approach the bottom of the glacier you should angle to the right, so you can get off the snow before coming too close to the lake below. Andrews Tarn is located directly below the snow, and if you slip near the lake you could easily slide right into the ice cold water. On the east side of the tarn you will find a rough trail that leads the last 0.9 mile down to the Loch Vale. Once you reach the Loch Vale Trail turn left, and 3.2 miles later you will arrive at Glacier Gorge Junction on the Bear Lake Road. From there you can ride a park service shuttle back to your car.


    The book includes more text, more photographs, and trail maps.

    If you are interested in a supplemental map of the Flattop Mountain and Hallett Peak area
    we recommend:
    Rocky Mountain National Park (Trails Illustrated, map #200)

    Click here for DISCOUNTED MAP ORDERS

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