This is given as the "Southeast Route" in Beckey's Cascade Alpine Guide.
From the Swede Heaven Road turn off from SR-530 (see Getting There section on Main Page), go north across the river to a T-junction. Turn left and go about 0.6 miles to a turn on the right. This is Forest Road 18. Drive FR-18 for 12.3 miles to Segelson Pass aka Deer Creek Pass (3,430 ft). There are a lot of spur roads getting to the pass but the idea is to stay on the main thoroughfare. Find the junction for FR-1850.
The remainder of the approach to the trailhead is supplied by kThurner:
"A ten minute walk from the junction of FR-18 and FR-1850 brings one to the begining of the Round Mtn trail. There is a large log pile on the left followed shortly by a pullout on the left. Across from this pullout the path leaves the road, though is is very, very obscure. It makes a rising traverse southward through the clearcut and becomes a distinct trail once it reaches the nearby old growth. When you are walking the overgrown road, the very first old growth encountered on the uphill side of the road is above a road blasted cliff. The path is a ways above this cliff."
A faint trail leads up the right side of a creek. The trail goes to a meadow then to the 3,800-ft saddle located 1 mile ENE of Round's summit. From the saddle follow a path along the ridge to Coney Pass (4,000 ft). Contour around the SE side of the mountain around a rock wall. After crossing a couple of talus fields, the path climbs up to the basin immdiately below the summit. Continue up through the basin to the summit (Class 2).
Time = 2 hours from the car. Distance = 1.5 miles. Elevation gain = 1,900 ft.
Ice axe if early season.
Appropriate clothing for the weather at hand.
Suitable brush whacking gear.
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