Elk Peak is the highpoint of the Castle Mountains. This small, isolated mountain range rises high above the central Montana plains just southeast of White Sulphur Springs. Elk Peak is located in the Lewis & Clark National Forest. It has a prominence of 2,768', and an isolation of 19.9 miles.
It appears that few outsiders ever venture into the Castle Mountains. A check of Peakbagger.com shows only seven registered ascents of Elk Peak as of November 2017. But for those willing to venture off the beaten path, an ascent of Elk Peak makes for a worthy objective.
From Hwy 294, at about milepost 15.6, you will see take the signed turnoff to Lennep. Zero your odometer. Drive 0.2 miles north, then make a sharp left turn. This is County Road 581, signed for Castle Town. At 7.6 miles, you will reach the Castle Town historical marker. Continue on the main road for 10.2 miles, where you will reach a road junction with Forest Road J-8884. This is marked by spot elevation 6860 on the topo map. Turn left and start driving up the rough, primitive road. After 12.3 miles, you will reach the end of the road at spot elevation 7663. ATV Trail 718 begins here. This is also where Forest Road J-8886 ends.
From the trailhead, start hiking up Trail 718. The route is obvious. Along the way, you will swing by Wapiti Peak just off to the right. Wapiti Peak is signed as Elk Peak #1. Continue south to Elk Peak, which is signed as Elk Peak #2. The trail ends just below Elk Peak. From here, you will have to climb 100' or so up a rock outcropping to reach the summit. This section is Class 2. There is a small building at the summit. The round trip distance is 8.4 miles, with 1,550' of total elevation gain.
External LinksPeakbagger.com Page for Elk Peak
Castle Mountains Wikipedia Page