OverviewCastle Mountain is the 3rd highest mountain in Montana. At 12,612 feet the mountain's appearance reflects it's title as a castle. The mountain's most common route isn't too technical to climb. The most popular route to the mountain is via the West Fork of the Rock Creek. The mountain is most accessible with crampons and an ice axe. Most people climb the mountain in two days.
Getting ThereWEST FORK of the ROCK CREEK TRAILHEAD
From the south side of Red Lodge Montana, turn West off of highway 212 and follow the road heading WSW across the plain and into the Rock Creek Valley. Follow the valley for 15-16 miles to the end of the road. This is the Trailhead leading up the West Fork of Rock Creek. The Rock Creek valley is popular for fishing, and several good camping areas can be found along the road leading from Red Lodge to the trailhead. From the trailhead, follow the path leading along the North side of the West Fork. After 7.5 miles you will reach tree line and a established bridge across to the South side of Rock Creek. Once you reach the bridge there are several good flat grassy areas to set up base camp. Such areas include Sundance Lake, Shadow Lake, or the Silt Lakes
LAKE FORK TRAILHEAD
From the south side of Red Lodge, Montana, follow highway 212 South for approximately 11 miles. Before passing Black Pyramid Mountain, turn right onto the well-maintained road which leads past several cabins and into the Lake Fork Valley. Follow this road for 2 miles to the trailhead. A footbridge crosses Lake Fork Creek just beyond the end of the road to join the trail on the Creek's south side. This trail follows the Lake Fork, passing by September Morn Lake near tree line after 8.0 miles. Sundance pass is another 2.0 miles from September Morn Lake. Cross over the switchbacks and set up base camp on the other side near any of the four lakes.
EAST ROSEBUD TRAILHEAD
This route is not as popular as the rest because it is more physically enduring to reach the spire due to climbing the Sundance Glacier.
When To ClimbThe main climbing season is early July to Labor Day.
DifficultyBased on the easiest route, which is also the route I've included I rate this mountain:
YDS Class 2: Simple scrambling, with possible occasional use of the hands.
CampingCamping is allowed anywhere within the Absaroka-Beartooth Wilderness. You are "requested" to check in with the Beartooth Ranger Station in Red Lodge or call (406) 446-2103 before camping (although most people do not bother). You must have a permit to cut live trees for firewood.
Most parties choose to climb Castle Mountain in two days, camping on either NW side of Sundass Pass in the bottom of the West Rock Creek valley or the SE side near September Morn Lake. If you camp along the West Fork Rock Creek side you have several areas to camp. There are many flat grassy areas near Shadow Lake, Sundance Lake, or the Silt Lakes. Remember, Leave No Trace, and as always in bear country, hang your food well away from camp at night.