Split Mountain is near the eastern most extent of the Uinta Mountains. It gets it's name because the mountain has been "split in two" by erosion forces from the Green River. The mountain is a huge anticline, which amazingly, the Green River has cut Split Mountain Canyon right through the center and highest part of the anticline. The setting is very spectacular because the bent rock layers and geology has been exposed. See this photograph taken of the eastern ramparts of the mountain. Note also that the USGS maps label just the northwestern half of the mountain as "Split Mountain". This is the part that will be covered on this page. In reality, JW Powell named both sides of the river Split Mountain, and locals also consider Split Mountain to stretch all the way from Red Wash on the west to Harpers Corner on the east. Despite being a rather locally famous landmark, the summit is very seldom visited. There are no trails up the mountain. Several scenic canyons cut through the south slopes of the mountain, which are made of a massive sandstone formation. There are several archeological sites on slopes of the mountain as well.
To get to the trailhead, you must first drive to the Dinosaur Quarry Visitor Center in Dinosaur National Monument, which is east of Vernal. Use a Utah Road map for the drive. After obtaining updated information (the visitor center will have no information on climbing the mountain itself, but is helpful on road and park conditions) from the visitor center, drive east on the Blue Mountain Road and turn left at sign for the Split Mountain Campground. The Desert Voices Nature Trail starts across the street from the campground. Park here.
There are no trails leading to either of the main summits of Split Mountain, but there are a few trails on the lower slopes and to various overlooks.
The Desert Voices Route is the route desribed that reaches the highest summit. It is a rugged route, and topo map is needed to follow this route. There is no trail after leaving the Desert Voices Nature Trail at Cottonwood Wash.
One the mountain, the only trail is the Desert Voices Nature Trail, which is very short and doesn't get remotely close to reaching the summit.
It appears that the mountain can be climbed from the north and the Island Park Road with equal difficulty than the south side and Desert Voices Route, but I haven't ever climbed that side of the mountain.
SP member Sagebrush writes in his summit log: I climbed Horse Trail Draw up to the saddle on the north half of Split Mountain. It was a bit of a scramble in some spots...especially near the park boundary.
The saddle itself was spectacular. It is undoubtedly a former side canyon carved long ago by a stream which eventually diverted around the mountain, since I found ancient stream deposits in the base of the saddle. It would be interesting to know the age of the deposit.
To get to the Horse Trail Draw, go on the road to Rainbow Park and look for the big notch (which is the saddle) in the mountain. Park next to the road and travel cross country until you reach the draw that leads up to the saddle. For directions to the Rainbow Park road, ask at a park visitor center.
Federal law protects all archaeological sites. Do not disturb them.
A free permit is needed for overnight camping in the backcountry.
Park entry cost $10 per vehicle in 2005.
Time Needed for Climb
The climb can be completed in one day.
When To Climb
The best times to climb this mountain are April, May, September, October, and early November. Summer is very hot, winter very cold. This route faces south, so expect it to be hot in summer, and the spring snows leave fairly early. See the weather chart below. These are just averages however, as in Spring or Fall you can either roast or freeze, often on the same day! This is a land of extremes and it is not uncommon to have the afternoon be sixty degrees warmer than in the morning. At the quarry, an average night in January is 4 degrees, and an average day in July is 95 degrees, but temperatures have been as low as -40 or as high as 110.
There are several campgrounds including the Split Mountain campground which is close to the trailhead, but it is now only a group site. Also close to the trailhead is the Green River Campground. For more information call the park headquarters at 801-789-2115.
Contact the rangers at the Dinosaur National Monument Headquarters at 801-789-2115 for updated conditions.