The 103,591-acre Henry M. Jackson Wilderness Area is accessible from the Stevens Pass [1], Skykomish, Lake Wenatchee, and Darrington [2] areas. It was named for a longtime U.S. senator from Washington, Henry M. Jackson, who was instrumental in helping establish wilderness areas throughout the West.
The glacier-carved landscape has a Swiss-Alps quality: numerous alpine lakes, prominent knife-edged ridges, and deep U-shaped valleys. Dozens of backcountry hikes are possible, and ambitious backpackers could continue on into the adjacent Glacier Peak Wilderness Area [3].
The Pacific Crest Trail passes through the center of Henry M. Jackson Wilderness before crossing Highway 2 and continuing on southward into the Alpine Lakes Wilderness [4].
An interesting and scenic 18-mile loop trek can be made by following the Beckler River Road (Forest Road 65) from the town of Skykomish [5] to Jack Pass [6] and continuing another mile to Forest Road 63. Turn right here, and proceed to the trailhead at the end of the road. The North Fork Trail (No. 1051) climbs into high mountain country from here, through masses of hillside wildflowers in midsummer, eventually emerging into the alpine after five miles or so.
It meets the Pacific Crest Trail at Dishpan Gap. Turn right and follow the PCT past Lake Sally and then back around 6,368-foot Skykomish Peak to the Pass Creek Trail, which will take you back to your starting point. Another option is to turn left at Dishpan Gap and follow Bald Eagle Mountain Trail (No. 650) back to trail No. 1050, which leads back to the road.
Contact the Skykomish Ranger Station (360/677-2414) for current conditions, use restrictions, and trail descriptions.
Links:
[1] http://www.moon.com/destinations/washington/north-cascades/stevens-pass-and-skykomish-valley
[2] http://www.moon.com/destinations/washington/north-cascades/mountain-loop-hwy/darrington
[3] http://www.moon.com/destinations/washington/north-cascades/mountain-loop-hwy/recreation/hiking/glacier-peak-wilderness
[4] http://www.moon.com/destinations/washington/south-cascades/snoqualmie-area/snoqualmie-pass/recreation/alpine-lakes-wilderness
[5] http://www.moon.com/destinations/washington/north-cascades/stevens-pass-and-skykomish-valley/sky-valley/skykomish
[6] http://www.moon.com/destinations/washington/north-cascades/stevens-pass-and-skykomish-valley/sky-valley/over-jack-pass