Black Tooth Mountain and Penrose Peak

Black Tooth Mountain and Penrose Peak

Page Type Page Type: Trip Report
Location Lat/Lon: 44.40300°N / 107.1787°W
Date Date Climbed/Hiked: Aug 10, 2008
Activities Activities: Mountaineering
Seasons Season: Summer

Planning the Trip

After climbing Cloud Peak in 2007 my wife Julie and I decided to try Black Tooth Mountain since it's the only other 13'er within easy driving distance of South Dakota. It also looked a lot more adventurous!

We checked the topo map and thought of starting at Willow Park Reservoir. When we finally got hold of a Bighorn National Forest ranger on the phone she told us there was only ATV access to Willow Park and Penrose Park. She suggested we drive up the Little Goose Road but said there was a major stream crossing at Little Goose Campground and that a crew was in the process of clearing logs from the road so we couldn't make it all the way to the trailhead. Since we wanted to drive there in our Corolla that left Bighorn Reservoir as the nearest starting point, and she told us we could park next to a gate at the lake's mouth.

Rocker Paully's route description and trip report were our only sources of detailed information, so we printed them out and took them along. We gave ourselves five full days because we didn't know exactly what to expect on the cross-country portions of the route. This gave us an opportunity to perfect our new light-weight backpacking strategy.

We drove nearly all night on August 7th then parked to sleep a couple hours on the Red Grade Road above the town of Big Horn (south of Sheridan) before making the final drive to the trailhead. We turned off of the Red Grade Road and drove to Park Reservoir with no problem, and then we took the road that climbed up to Bighorn Reservoir. It became far too steep and rocky for a compact car, but with several spinouts and encounters with rocks we managed to meander our way up. Then we ate granola and packed our packs and were ready to start.

Day 1

Bighorn ReservoirBighorn Reservoir
The trailhead at Bighorn Reservoir is very confusing, and we got off to a terrible start. The topo map shows a trail going around the west side of the lake and continuing on to Cross Creek Reservoir, but the Solitude Trail that we wanted to take branches off between the two reservoirs. We also found a prominent trail along the east side of Bighorn Reservoir that appeared to be a shortcut to the Solitude Trail, so we took that instead. It branched several times and we ended up in a bog along the south side of the lake. We found a road that crossed the creek to the west and took the road to Cross Creek Reservoir, but we never found the Solitude Trail. The road ended at Cross Creek Reservoir so we headed east cross country up a steep, rocky hillside in hopes of intersecting the Solitude Trail. It was a rough route over a boulderfield and several brushy creeks, but we finally found it. (On the way back we found where we had gone wrong. The key is to stay on the most well-beaten trail east of Bighorn Reservoir rather than dropping down to the lakeshore.)
Cross Creek ReservoirCross Creek Reservoir

Once on the Solitude Trail it was easy traveling into the higher mountains. We passed a group on horseback and a boy scout (with two adults) who had been at the Little Sioux Scout Camp when the tornado killed several scouts earlier in the summer. But for the rest of the trip, until we returned to Bighorn Reservoir, we didn't see another soul.

After about three miles on the Solitude Trail things became confusing again because the trail was not as indicated on the topo map. Near a point at 10,370 feet elevation the trail does not continue heading south over a pass but instead turns east and drops down to cross the head of East Fork Little Goose Creek before climbing back up to Highland Park. The benefit of this "new" route is that it stays at a more constant elevation and crosses a nice source of water.

Highland ParkHighland Park
Highland Park is amazing in being so large and flat--and it became an obvious landmark for the rest of our trip. It also provided the first good view of Black Tooth Mountain and the other dark, jagged peaks that surround it! We took the trail south across the park toward Highland Lake, and eventually the trail dropped steeply down to this lake. We continued on the trail until it crossed the creek that exited the lake, but then things became confusing again. The trail to Highland Lake is not on the map, and it seemed to be heading toward Kearney Lake which was not where we wanted to go. We wanted to head south to Princess Falls that drain the Sawtooth Lakes (west of Penrose Peak).
Highland LakeHighland Lake

We headed south cross country and ended up in some rocky crags in the forest. Several times we came upon a large trail and followed it for a while only to have it disappear again. Soon the waterfall came into view so we headed in that direction and ended up on a trail again. Before crossing Kearney Creek we stopped and camped for the night.

Day 2

Lower Sawtooth LakesLower Sawtooth Lakes
August 9th was a long day of cross country hiking and climbing. We began by crossing Kearney Creek and locating a trail/route that ascends the west side of Princess Falls up to the Sawtooth Lakes. The ascent wasn't too difficult and provided a spectacular view of Highland Park. But we encountered a problem above the waterfall when the trail ended at a creek that required wading and climbing over logs. Once again we were off the trail and making slow progress. (On the return we found a better way farther west.) Eventually we found a trail again, but it wasn't consistently good.

InnominateInnominate and Mount Woolsey
The Sawtooth Lakes are beautiful, as is the jagged sawtooth ridge above them to the east. The west side of the canyon is also a sheer wall, and we watched several rockfalls crash down. The curvature of this canyon blocked our view of Black Tooth Mountain most of the day, but there was plenty to see. There are ten sawtooth lakes in all, and we climbed and traversed around all of them. The upper ones still had some ice cover. Eventually the trail disappeared entirely, and we also had to cross some snowfields.
Tenth Sawtooth LakeUppermost Sawtooth Lake

We hoped to camp at the uppermost Sawtooth Lake, but it was a small icy mess in a deep, steep depression in the middle of a giant boulderfield. It had nothing to recommend it as a campsite. Above it was a steep field of layered ice--probably the last remnant of a former glacier. Flat ground was hard to find, but we maneuvered the boulderfield to the base of Black Tooth Mountain and moved enough black sand to pitch our tent near a stream. We were perfectly positioned for our summit ascent the next day.
Black Tooth 02Black Tooth Mountain

Weather was a concern, and we had a brief hail storm that drove us into our tent for a while. But then it cleared up and was a pleasant evening. The rocks were full of pikas and marmots. I left Julie and made a late climb southward up a ridge toward Hallelujah for a better view of Black Tooth Mountain above and the Sawtooth Lakes below, and I returned after dark by flashlight.

Day 3 - Black Tooth Mountain

We left our camp with a day pack and crossed a small snowfield to begin our climb up Black Tooth Mountain by the Northeast Ramp described by Rocker Paully. The steep ramp is formed by a dike of mafic rock that erodes faster than the surrounding gneiss.
Black Tooth 14Climbing the ramp
It appeared from below to be the best route, but it was hard to determine its difficulty without being on it. The ramp was steep and required considerable route finding in places, but there were only a few spots that were exposed and difficult to climb. We had to be careful not to knock rocks on each other. Another option was a snowy ramp just to the east, but we decided to stay on dry rock.

Rocker's report mentioned a rope anchor, and we brought a short rope along in case we needed it. After ascending a steep, narrow chute where I had to give Julie a boost we found it. (On the way down I even convinced her to downclimb it without the rope.)

Above this steep chute the slope was not as steep and the terrain was more open. It was just a rocky scramble up to the twin summits of Black Tooth. The east summit looked higher, but we knew it was the west one we were after. The view from the summit was spectacular, especially of the flat-topped Cloud Peak to the south and the many lakes in valleys to the west. We hurried to eat lunch and take photos because the weather was threatening and a storm was predicted for later in the day. We had achieved our main goal.
Black Tooth 05Cloud Peak from Black Tooth

Downclimbing the ramp was no more difficult than ascending it, and we reached our tent in the early afternoon. After packing up and photographing a friendly marmot we started down the canyon, this time taking a snowfield on the west side of the canyon to avoid the difficult boulderfield around the highest Sawtooth Lake. In several places we took a different route around the lakes than we had on the way up.
Black Tooth 20Third Sawtooth Lake

Since we were tired from three long days of hiking and still had a couple days remaining, we stopped well before dark and camped at the third Sawtooth Lake on a perfectly flat spot of ground next to a giant boulder. The storm had passed without much action and the sky was clear and deep blue. As we began to feel rested the idea of climbing Penrose Peak, looming in the crags above us to the southeast, got into our heads, and we planned a route to ascend it the next morning.
Black Tooth 19Sawtooth Ridge

Day 4 - Penrose Peak

Penrose Peak 6Black Tooth Mountain from Penrose Peak

From the third Sawtooth Lake we climbed a boulderfield heading northeast around the base of a cliff to gain access to what looked like a nice sloping ramp up Penrose Peak. The boulders became large and hard to cross, but travel became easier on the ramp and included some grassy areas. The peak was obscured by many false summits, or rather by endless hummocky boulderfields. The rocks became very large once again and were steep in places. But we continued climbing up to the south until the large summit cairn came into view.

Penrose Peak provided a unique and spectacular view of Black Tooth Mountains and surrounding peaks, of the Sawtooth Lakes, and of Highland Park and all the lakes to the north. The distinctive plateau of Cloud Peak was even visible over a pass. It was difficult to leave the peace of the summit and return to the endless boulder crawl that awaited us. There was no other option on the first part of the descent, but when we got to the meadow farther down the ramp we decided to descend to the lowermost Sawtooth Lake rather than the third one to avoid the boulderfield we had first climbed in the morning. It was definitely a better route even though we had to take the trail back up to the third lake to retrieve our tent and gear.
Penrose Peak 7Cloud Peak Reservoir

In the afternoon we descended the Princess Falls down to Kearney Creek and tried once again to find a trail from there to Highland Lake. But once again the trail appeared and disappeared, and we spent most of the time following a GPS track. When we arrived at Highland Lake we met a large moose browsing in the bushes by the creek, hardly bothered by our presence..
Princess FallsPrincess Falls

We filled all our water bottles at Highland Lake in preparation for a dry camp then made the steep ascent to Highland Park. We crossed the park in the low evening sunlight, often looking back at the looming black peaks behind us. We camped at the pass at the north end of Highland Park and found some trees to the west of the trail to shelter us from the wind
Black Tooth 22Highland Park

Day 5

Highland Park was a fun place to wake up since it provided a clear and early view of the rising sun and a spectaculr view of the high summits. The hike down the Solitude Trail seemed longer than on the way up because we were so tired from four days of hiking and climbing. But we still felt like we had the whole mountain range to ourselves. We crossed East Fork Little Goose Creek and descended the trail toward Bighorn Reservoir. Once again it was difficult to tell which of several trails to take, but the main one (not on the topo map) led us along the east side of Bighorn Reservoir to our car. This time Bighorn Reservoir was crowded with fishermen and people taking short strolls.
Black Tooth 23Black Tooth Mountain

Driving down to Park Reservoir was more difficult than driving up, and we got high centered once and had to build a rock ramp to get the car moving again. We wished we had just hiked from Park Reservoir (adding 1.5 miles and 500 vertical feet) to avoid this hazard.

We drove to the town of Buffalo and stopped at a ranger station for a forest map, hoping it would have updated trails from the 1967 topo map. But the newly-printed maps had all the same trail errors and were no help at all. We consoled ourselves with big ice cream cones at a little ice cream stand! We drove to Rapid City for the night then paid a visit to the tiny town of Faith to see the exhibit of Sue the Tyrannosaurus before heading home to Siouxland.


Post a Comment
Viewing: 1-19 of 19

musicman82 - Feb 16, 2009 1:23 am - Voted 10/10

Interesting reading!

It's always good to see trip reports from the Big Horns - I'd love to see this page with some pictures! You should probably delete the other two incomplete pages that you posted of this report:

Best wishes,


Heaton - Feb 16, 2009 1:46 am - Hasn't voted

Re: Interesting reading!

Thanks. I'm still creating the page and have lots of pictures to add. I'm also learning the ropes of this site. Posting pictures and arranging them has its difficulties.



musicman82 - Feb 16, 2009 1:55 am - Voted 10/10

Re: Interesting reading!

Great - I'm looking forward to seeing the finished page! One thing you might do would be to put "Under Construction" in the title of the page to let people know that you're still working on it; that way you don't get bad votes and stuff...


Heaton - Feb 16, 2009 11:20 am - Hasn't voted

Re: Interesting reading!

Okay, it's finally done ... complete with photos. It was fun reliving that wonderful trip while making this page!


SLinehan88 - Feb 16, 2009 1:36 pm - Voted 10/10

Very helpful

Great trip report. I love visiting the Big Horns. I was talking with a forest ranger last summer in Buffalo and she suggested this area if I wanted to avoid the crowds. I guess the trade-off for avoiding crowds is sketchy trail maintenance.



Heaton - Feb 17, 2009 3:17 pm - Hasn't voted

Re: Very helpful

Thanks. Yes you are correct on all counts. When we climbed Cloud Peak in 2007 there were groups camped everywhere and a ranger checked our permit. On the north end we saw practically no one. There are plenty of remote valleys and peaks to explore up there. I made a point of filling my report with information that would have been helpful to me on my trip.



D-bo - Feb 19, 2009 9:17 pm - Hasn't voted

Great info and pics

Glad to know you climbed Black Tooth without any climbing gear. I'll try it next time I visit the Bighorns.

Rocker Paully

Rocker Paully - Feb 20, 2009 10:16 pm - Voted 10/10


I'm glad I could help you up that peak, now you gotta do Woolsey!
It's a Grade IV 5.7 if you go left of the snow ramp from the base. We did it in 11 pitches, super fun.


Heaton - Feb 20, 2009 11:52 pm - Hasn't voted

Re: sweet!

Thanks Rocker. Your report was a great help to us but still left room for the unknown. It's nice to hear from you. Woolsey does sound tempting! Have you written it up?

Rocker Paully

Rocker Paully - Feb 21, 2009 12:27 pm - Voted 10/10

Re: sweet!

Nah, I figure it's better to keep that one on the down low, lots of first accent possibilities still. Hallelujah is the same way, I'll write up a page on them one of these days, I just don't have the time now. It would suck if Penrose Canyon and Wilderness Basin started getting the traffic that the Misty Moon Lake area gets. I know I've spent 6 days in the area north of Black Tooth and haven't seen a soul, kinda nice.


pcole8787 - Dec 4, 2019 4:00 pm - Hasn't voted

Re: sweet!

I have. I think sharing mt experiences should not be tainted by the idea that now that I have mine, you should figure it out for yourself. There is alot more to contend with on an adventure like this. A trip report can be brief and informative. I don't see any way that it would spoil it for others. It's a long walk into Woolsey not matter which way you go. If I can help any interested parties, I am more than willing to do so. My trip report can be found at:


mickey - Feb 22, 2009 11:24 am - Hasn't voted


I've never been to the Bighorns but have always heard they're gorgeous. Some of your shots remind me of the Winds. I'll have to get over there. Thanks for sharing!


alpinedon - Feb 22, 2009 12:46 pm - Voted 10/10


don't know much about this area, so it was really interesting to read. Nice write-up!


seanpeckham - Feb 23, 2009 4:15 pm - Voted 10/10

Congrats on featured trip report



christytoes - Feb 23, 2009 7:49 pm - Voted 10/10


Great trip report with gorgeous photos!

climber55527 - Feb 24, 2009 8:47 pm - Hasn't voted

right on

good job on the climb. I will be attempting woolsey and black tooth this summer.


Dean - Feb 25, 2009 1:29 pm - Voted 10/10

Great TR

I did Cloud Peak this summer and enjoyed the area (except for the mosquitos) Beautiful scenery in that area and your write up is
food for thought (for a return to the area) Nice effort.


rebderr - Jun 26, 2013 9:10 am - Voted 9/10

Thank you!

Late review BUT... just what we needed to find. Black Tooth isn't well covered and although a bit of adventure and mystery is nice an all... some source- work is awesome to have! We leave this Friday and I'm stoked to climb Blacktooth esp. now that I've seen it in print that this can be done without roping up.
I climbed Cloud Peak 25yrs ago and the ridge above Cliff Lake about 7yrs ago both times staring at Blacktooth intending to come back for it someday :) Welcome to someday! We'll be bringing your report along with us!


Heaton - Jun 27, 2013 10:08 am - Hasn't voted

Re: Thank you!

Good luck with your trip! Be safe.

Viewing: 1-19 of 19



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