This trail starts across from a small pull-off parking area on Dry Creek
Road / NF-64, which is paved but narrow. The trail drops a bit and in only a few hundred feet you'll come to Dry Creek
-which is definitely not dry at least in the wet season.
As of 2020 there was no bridge nor any log/stone crossings so you'll have to forge this creek. Note that in early spring it can be quite swift! By late summer crossing should be an easy jump or two. The creek does act as a barrier to many so this trail gets very few visitors and can provide nice solitude. The lack of visitors also means less maintenance so be prepared for some blow-down.
After the creek you'll see the end of Dry Creek
Trail, enter the Trapper Creek Wilderness, and start climbing. From the creek to about the 2 mile point is pretty steep, but the trail is well made. You'll pass the occasional old growth along the way. A little after the two mile point the trail levels out in an exceptional strand of old growth near another creek that creates a small unnamed falls.
The trail climbs a bit more before arriving at Observation Trail #132
You can take Observation Trail #132
less than half a mile south to the Observation Peak Trail #132A
which leads to the summit of Observation Peak to get the amazing views that Big Hollow #158 lacks itself.