Sinister is an attractive, if asymmetrical, ice-clad peak deep in the Glacier Peak Wilderness Area. Previously, Sinister was a strong candidate for the most remote of Washington’s 100 highest mountains, but with the reopened Suiattle River Road, it can be done in 3-4 days.
Located almost 1 mile east of dominant Dome Peak, Sinister is a sharp, granodiorite summit bordered by the huge Chickamin glacier on the north, the Garden Glacier on the south and an unnamed body of ice to the east. The north face is steep ice, the south face is a short but steep rock climb. The east ridge is studded with spires and the northwest face or west ridge yields the easiest ascent.
All approaches to Sinister are long and taxing, even by Cascade standards. The successful suitor will face many miles of trail, challenging route-finding to avoid heinous brush, and massive elevation gain. A natural strategy would be to climb the peak in the course of the magnificent Ptarmigan Traverse
Crossing Bachelor Creek at 3700'
Cub lake and Itswoot Ridge (highest green) with Dome behind. On summit day, you'll aim to left of the summit of Dome Peak in order to reach the Chickamin Glacier
The standard approach is from the west via the Downey Creek Trail and Bachelor Creek route. With the Suiattle River Road finally repaired, this approach is still 15 tough miles to high camp (down from 23 miles when the washout hampered access). Drive State Route 530 north from Darrington or south from Rockport and turn east on the Suiattle River road No. 26. Drive this road 19.5 miles to Downey Creek Campground and the original trailhead, elevation 1450'. Subsequent mileages from this point. Hike the Downey Creek Trail 6.5 miles to Six Mile Campsite (2440'). Continue up the unmaintained Bachelor Creek route starting on the north side of the stream but crossing to the south at 9.5 miles (3700').
The route continues (be attentive!). At 4500' a big 2002 avalanche
wiped out the trail and travel will be difficult through this area. Eventually the brush thins into open timber. There is good camping around a side valley at 11 miles and below a pass. Cross over the pass (~5900') NW of Cub Lake and descend to the lake (good camping, 5338'), 14 miles. Continue following the tread around the lakes and steeply up to Itswoot Ridge and stunning camping (6400' or 6900' 15 miles and 5500' vertical). Congratulations; you've completed the approach!
An alternative approach (short in terms of miles) is perhaps from the east. From Stehekin take the bus to the Agnes Creek trail and follow it about one mile past Swamp Creek (approximately 9 miles from the trailhead) and then use the Agnes-Spruce Creek Route (see Becky CAG v2 and Goldman). This route will likely involve tortuous brush and will likely take longer than approaching from the West. I don’t advise it, but I’d love to hear from you if you are brave enough to try it.
A Northwest Forest Pass is probably required at the trailhead (available from some stores and at nearby ranger stations). The pass can also be purchased online from the Washington Trails Association. A free wilderness permit is available at all trailheads. Party size is limited to 12 within Glacier Peak Wilderness.
Northwest face: From a camp on Itswoot ridge, traverse east across heather and scree, rising to meet the Dome Glacier on its northwest side. See this photo
. Ascend to the N shoulder of Dome ~8500’ (good bivy sites to the south at 8700') and descend the Chickamin Glacier
(crevasses) until about 7200' where you can traverse right and climb to the 7640’ Dome-Sinister col; a 'shrund may pose problems in late season.
From the col, Stephenson & Bongiovanni advise climbing moderate snow on the NW face until an easy scramble yields the summit as shown here
(See "Summit Routes: Washington's Highest Mountains")
West ridge: Becky suggests continuing from the col to the south side of Sinister's west ridge under a notch, then climbing a dirty gully to the ridge followed by steep, exposed snow and a final easier scramble. See photo
. Class 3 and steep snow. (see Becky CAG vol 2)
North face: reputed to be a very attractive (50 degree max) snow and ice climb (see Nelson & Potterfield vol 2 and this photo
East ridge: class 5 (see Goldman "Washington's Highest Mountains")
South face: 300’ of class 4 (see Becky CAG vol 2)
When to Climb
One could probably climb Sinister between May and October, but July and August would likely be best.