#157 / 13,684' Mount Oso

Range › San Juan Range
Quadrangle › Emerald Lake
Summit Location › Peak Route Icon N 37° 36' 25.12", w 107° 29' 37.19" (Not Field Checked)
Neighboring Peaks › Peak Icon "Mount Soso" Peak Icon Irving Peak

Peak Summary

For those wanting to complete the two hundred highest summits in the state, Mt. Oso will prove to be the most distant and difficult to reach. The climb of the peak itself only receives a Class 2 or 2+ rating depending on route taken, but getting there is the problem. The Beartown/Kite Lake trailhead will be the closest vehicle access and requires 4WD with good clearance. Then there's backpacking into Rock Lake, a full day trip for most. The peak can also be climbed from Moon Lake. With so many other 13ers in the neighborhood, it's best to plan a multi-day backpack trip.

Mt. Oso SE Ridge Route

Class 2+
backpacker icon + Peak Icon
Backpack + Medium Day
RT From Bear Creek/Hunchback Pass/Kite Lake: 25.3 mi / 7,100'
RT From Rock Lake: 5.5 mi / 2,300'
  • Trailhead
    • Bear Creek/Hunchback Pass/Kite Lake Trailhead

      WARNING: This trail head approach REQUIRES 4WD with good ground clearance. The drive as described below from Silverton may take up to 2.5 hours.

      From the Town of Silverton, and where the main road splits at the NE end of town, drive 4.2 miles NE up along the Animas River on blue-signed County Road 2 to Howardsville. Turn right onto FR589 up Cunningham Gulch and stay right at the turn for the "Old Mine Tour" (4.4 miles) but do take the left fork toward Stony Pass (FR737) at 5.9miles. Once on the Stony Pass Road, expect 4W conditions. The road climbs steeply to the pass. Abundant wildflowers as you approach the pass may delay you. Once across the pass, the road becomes FR520 and eventually leads to Rio Grande Reservoir, but you will not drive that far. The road eventually descends down the valley to a low water crossing of Pole Creek. Watch out for the steep embankment climb out on the other side if the road is wet from rains. You could easily slip off the edge. After the crossing, continue south for about a mile to another fork where you'll turn right (west). Another long, low water crossing is found here across the Rio Grande River. This crossing is usually more shallow than the Pole Creek, but the closer you are to runoff season, the more difficult these crossings will be.

      It is also possible to come into this area from either Creede or Lake City over Slumgullion and Spring Pass to Rio Grande Reservoir. From state highway 149 either about 20.5 miles from Creede or 32 miles from Lake City, turn west onto FS520 and drive all the way to the reservoir on the well-signed, graded dirt road. Passenger cars can make it all the way to the "Lost Trail Campground" at the far west end of the reservoir. Beyond that point, FR520 continues west and crosses some rugged sections before connecting with the other section of FR520 coming down from Stony Pass and the low-water crossing of the Rio Grande. We have never driven in all the way on this section and from those we know who have, they have complained about one particularly difficult stretch.

      From the Rio Grande crossing, continue up what is now, the Beartown Road for a slow 7 miles (mainly because of potholes). The road goes all the way to Kite Lake at about 12,100 ft., but the Hunchback Pass trailhead is about 1/2 mile below the lake. There's a trail sign there and some very limited parking is available. Note: There was a fairly difficult section of road around the Beartown site due to muddy potholes.

      As the road begins climbing more steeply toward Kite Lake and the Hunchback trailhead, it becomes quite a bit more rocky in that stretch as well.  If you have driven in here to do the Ute Ridge group of summits, camp in the vicinity of where the road crosses Bear Creek just past the old Beartown site. See coordinates below. From that creek crossing, it's not quite .3 mile to the trailhead for Ute Ridge, which is a jeep track that turns off to the left and drops down to cross another lesser fork of Bear Creek. Park somewhere along this track if heading for Ute Ridge. On the Caltopo map, this trail is called the "Bear Town Trail" and designated FR869. On trails Illustrated Map #140, it does not appear to have a designation.  Coordinates for this road & trailhead are: N 37° 42' 54.53"  W 107° 30' 35.00"


      Camping

      You can find some very limited camping spots in the immediate vicinity of the Hunchback trail head. There's one particularly good spot back down the road a fairly short distance on the south side. There's also some good camping back toward the Beartown site. See coordinates provided.


      Campsite Locations

      Beartown Campsite › N 37° 43' 05.02", W 107° 30' 35.47"
    Approach Maps Photos
    • From Bear Creek/Hunchback Pass/Kite Lake TH via Rock Lake

      • Hunchback Pass to Nebo Creek  Moderate | RT: 5.5 mi / 1,900’

        This "approach" is part of a sequence of approaches that utilize the Vallecito Trail beginning near Kite Lake and above the "Beartown" site. The trailhead is located at: N37° 42' 44.57"  W 107° 31' 04.97". Use the "Beartown/Kite Lake/Hunchback trailhead information for instructions on how to drive to the TH.

        The trailhead is actually within the Rio Grande National Forest. The TH number is #813 on both the San Juan and older Rio Grande National Forest maps and is a part of the "Continental Divide Trail" at this location and segment. Once the trail crosses Hunchback Pass, it crosses over into San Juan National Forest and becomes #529, continuing south all the way to Vallecito Reservoir. If using Trails Illustrated #140, they identify this as the Continental Divide Trail and use the #813. Walk south from the TH and follow the easy gradient through open terrain with some willows to Hunchback Pass. The trail first sweeps SE, then makes a gradual turn SW, then west to the open, tundra-covered pass with about 900 feet of gain over just under a mile. Coordinates for the pass are: N 37° 42' 16.62"  W 107° 31' 12.37". Hunchback Mountain is west along the divide and can be easily climbed by those interested in bagging all the 13ers. You can drop your pack, stroll to the summit and return in under an hour.

        From Hunchback Pass, continue south heading straight down an unnamed fork of Vallecito Creek. The trail cuts trough plenty of willows in this section and stays on the west side of the drainage until just before the trees. Because of the numerous willows, plan on getting pants & boots drenched if it has rained recently. Also, as a general point, the Vallecito Trail is utilized regularly by pack horse groups so you can expect to see and experience some of the typical trail damage done by horses. The trail then turns to the SE and comes to an intersection. A newer trail (#813) that does not show on the 1964 USGS map heads east up Nebo Creek, crosses the Continental Divide and goes to West Ute Lake. That is the continuation of the Continental Divide Trail. The Vallecito Trail continues south and west from this intersection. Near the trail intersection, there is a very large and good campsite on a prominent knoll above Nebo Creek on the NW side. The campsite makes a good base camp for 13ers off the CD trail including Mt. Nebo, UN13,110, UN13,230, and UN13,169, all of which can be done in a single day from the campsite. See "Camping info" for more details.



        Camping

        The Nebo Creek campsite sits near the intersection of the Vallecito Trail and the Continental Divide Trail. The elevation is appx. 11,500 ft. Coordinates are below. They are something of a guess by using Google Earth, but the campsite is right off the main trail. There are several good tent spots and large logs near campfire areas. The creek is a short jaunt down the hill.

        Campsite Locations

        Nebo Creek N 37° 41' 12.36", W 107° 31' 14.88"

        Open This Approach in a New Window
      • Nebo Creek to Trinity Creek  Moderate | RT: 2.5 mi / 1,000’

        This "approach" is part of a sequence of approaches that utilize the Vallecito Trail beginning near Kite Lake and above the "Beartown" site. The trailhead is located at: N37° 42' 44.57" W 107° 31' 04.97". Use the "Beartown/Kite Lake/Hunchback trailhead information for instructions on how to drive to the TH.

        From the Nebo Creek campsite and the trail junction of the Continental Divide Trail #813 and the Vallecito Trail #529, head south down the Vallecito Trail. The trail swings to the west through forest, staying well above Nebo Creek and then makes an abrupt turn back to the south to cross Nebo Creek. We have usually found this crossing to be a little difficult and somewhat intimidating. The water is swift and nearby the stream heads over the beginning of a waterfall. Sometimes there are logs you can walk across on and other times, there's little help. You may have to wade.

        After crossing Nebo Creek, continue downhill, through a series of switchbacks and at 1.25 miles from the Nebo campsite, you should come to an open meadow on the right (west) side of the trail and see a secondary trail heading over to a crossing of Vallecito Creek, below where Trinity Creek comes in. This meadow area is often used as a camp spot by various groups, though it tends to be a little lumpy. From this location climbers can reach The Guardian, Mt. Silex, Storm King, and Peaks Seven, Eight and Nine as day hikes/climbs. But if you're willing to lug your pack back uphill, read about other higher elevation campsites under the "approach" for those peaks.  If hiking back up to the Nebo Creek camp or back over Hunchback Pass to the trailhead, this section from Trinity Creek back to Nebo Creek is the steepest part of the return hike gaining about 1,000 feet in elevation. It is also possible to hike all the way up Trinity Creek and cross the ridge that separates the Trinity Basin from the Vestal Basin and access the Vestal Creek summits.



        Camping

        An easily identifiable trail turns west off the main Vallecito Trail and leads over to where you can cross Vallecito Creek, downstream from where Trinity Creek comes in. This trail leads across an open meadow that is frequently used as a camp location. See approximate coordinates below.

        Campsite Locations

        Trinity Creek N 37° 40' 33.01", W 107° 31' 27.89"

        Open This Approach in a New Window
      • Trinity Creek to Rock Creek  Easy | RT: 3.5 mi / 400’

        The 1.75 mile walk from the Trinity Creek camp to the crossing of Rock Creek is an easy, quick jaunt down the trail that will take under an hour with only about 400 feet in elevation loss. Though the trail starts out in forest, it crosses plenty of open valley terrain before re-entering forest for some broad switchbacks that make the final drop to the Rock Creek crossing. We have never found any useful logs to cross on here, so be prepared to wade, and at the crossing point, the stream widens out so the wade is long, but usually not challenging. If heading up to Rock Lake, you will not need to make the crossing. The Rock Lake Trail stays on the north side of Rock Creek. Vallecito Creek from the Trinity Creek intersection and heading downstream begins to offer attractive pools and stream fishing opportunities.

        The Rock Creek trail #655 provides access to Rock Lake, a seemingly popular destination for horse-pack groups. From a possible base camp location near Rock Lake, the following 13ers can be accessed, most of which are found on the Columbine Pass and Emerald Lake quads: UN13,302, Irving Peak, Peters Peak, UN13,222, UN13,220, Mount Oso, UN13,417, UN13,310, and UN13,340.



        Camping

        In past visits, we have not found very good campsites at this crossing, though you can certainly find spots to "make do." Perhaps some have developed by now. Better sites may be found south of the crossing in the open meadow area over toward Vallecito Creek.

        Open This Approach in a New Window
      • Rock Ck to Rock Lake  Moderate | RT: 8.3 mi / 1,500’

        From Rock Lake, the following summits can be easily reached: Peter's Peak, UN13,222, and UN13,220. Mt. Oso can be easily reached from either Rock or Moon Lakes. From Moon Lake, UN13,310, UN13,340, UN13,417 and Irving Peak are most easily accessible. UN13,302, which barely makes it onto the SE corner of the Storm King quad, can be accessed from a couple miles up the Rock Creek Trail. Read the route description regarding that summit for more detail. We have hiked on this trail twice - once in 1994 and then again in 2004.

         From the Vallecito Trail, the Rock Creek/Lake trail heads ESE, on the north side of Rock Creek, gaining some 900 feet in elevation steadily but not too steeply the first mile and a quarter. It then enters an open valley at about 11,100 ft. still following on the north side of the creek and staying close to but not in the trees. Through this open valley section, the elevation gain is gentle. The trail is well-established and frequently used by pack horse groups. The first meadow section ends soon followed by a longer meadow stretch. Rock Creek meanders its way through this meadow with a few "tree islands" in the middle of the meadow toward its upper end. Granite rocks along the valley floor have been planed off by long-past glacial action leaving large slabs exposed. There are many camping opportunities along the meadow stretches, though we saw few established camps and those we saw were used primarily by the pack horse groups. One of the "tree islands" had a good campsite. Buffalo Peak makes a dramatic, sharp-pointed appearance towards the head of the valley and dominates the view. In 1994, there was a trail fork at 11,480 feet just before a crossing of Rock Creek. Stay right for Rock Lake and cross the creek if that fork is still there. The more recent Trails Illustrated map shows this fork higher up and closer to Rock Lake now. Finish the hike and last elevation gain to Rock Lake on fairly gentle switchbacks. A little before exiting the trees in this switchback section, there was a tree-covered ridge sloping back down toward the valley on the left side of the trail and on the south side of Rock Creek that offered some very attractive campsites. (This is about 10 - 15 minutes walking below the lake.) This would be the last opportunity for tree camping before the lake.

        Rock Lake is a beautiful and large alpine lake that sits nestled in a bowl at the foot of Peters Peak. It is surrounded by willows and grassy meadows which may obscure the trail. The best camping is back down the trail as we described.



        Open This Approach in a New Window
    Peak Icon Route Map Photos

    Route Info Mt. Oso SE Ridge

    Route Description

    Year Climbed: 1994

    Mileage and elevation gain estimates are based on a start from the suggested campsite below Rock Lake. Add 300 feet of additional elevation gain on the return to camp. If climbed from Moon Lake, the round trip mileage from that camp location would be 4.0 and the elevation gain would be 2,060 ft.

    From our suggested campsite, follow the trail on up to Rock Lake and continue south on the trail, past the lake and up to a small pond at 12,100 ft. Continue on the trail as it passes through some talus and follow it to the pass at 12,420 ft. where you can look down upon Half Moon Lake. The trail continues west, gaining a little more elevation, then takes a turn south to descend to Half Moon Lake. Depart the trail at that turn and continue walking WSW over a low and broad ridge. On the west side of the ridge, drop down into a mostly tundra-filled basin losing around 300 feet elevation. There is abundant grass and wildflowers through here. This large basin on the east side of Oso slopes down toward Moon Lake.

    Work WSW across the basin aiming for a prominent talus slope that descends off the peak that generally faces east & SE. This talus slope fans out in the lower portion of the valley and is very prominent. Head up that slope, aiming for a break in the SE ridge of Oso. Some tundra along the edge of the talus can aid in finding stable footing. Watch for a slope on the left that opens up and allows access to the SE ridge. (One could also head across this large basin and aim for the saddle between Oso and Soso. There are actually two low points of nearly equal elevation. We saw no point in going that far south.)

    Once you've ascended the talus and gained the SE ridge of Oso, simply head NNW following the ridgeline on the west side. Earlier in the season, you may have snow to deal with, hence the indication for ice axe. Ascend steeply at first on large, loose, broken boulder talus, passing a narrow and spectacular notch. Above the notch, things level out some and you'll be walking more on what we call "dinner-plate" talus. The smaller, flatter pieces of rock sound like you're walking on pieces of china. The true summit now becomes visible and you can finish on mostly Class 2 rubble. We rate ascending the talus cone as Class 2+, but it's been many years since we've climbed this summit. Enjoy the amazing view, particularly to the west where Jagged Mountain will certainly arrest your attention. The Sunlight Creek Basin does not appear to have a flat place in it, but views from this far away are deceiving. Return as you came.

    We will also point out that Mt. Oso can be climbed in a single day from the Beartown/Kite Lake trailhead as attested to by our long-time climbing partner, Fred Askins. In 1993, while we were climbing White Dome and Peaks One, Two and Three from Kite Lake, Fred departed at 4:30 AM and made the 22 mile roundtrip hike with over 6,000 feet of total elevation gain and managed to return to us before the sun set. Do not attempt if you have any doubts about your own conditioning.


    Additional BETA

    Links to other information, routes & trip reports for this peak that may be helpful.
Warning! Climbing peaks can be dangerous! By using this site and the information contained herein, you're agreeing to use common sense, good judgement, and to not hold us liable nor sue us for any reason. Legal Notice & Terms of Use.
Donate to Climb13ers.com ›