Route: Glacier Peak (WA)

summitpost.org:

Glacier Peak (10,541') is one of the five volcanoes of the state of Washington, and is the highest mountain in Snohomish county. It has 7498 feet of prominence and ranks 5th highest on the Bulgar List (Washington Top 100). It is located in the North Central part of the Cascades which it has a wilderness named after this mountain which is called the Glacier Peak Wilderness. The Native Americans once called this peak Takobia which would translate to "The Great Parent". This peak is classified as a stratovolcanoe (Composite) which there has not been any major activity in 300 years. This peak goes unnoticed by much of the people of the Northwest due to it being so far in the crest of the Cascades, its distance from the nearest town, and the fact that its access roads have been washed out making all the approaches to its base a long hike in. Glacier Peak can be seen from many locations along the Mountain Loop Highway, North Cascades, Highway 2 area, and many other high points through out the state. But this peak is often hidden from view from many low land areas which is another big reason it goes unnoticed by many. The summit offers amazing views of many of the great peaks of Washington, as well as a view of seeing far across the state.

Sean O'Rourke noted some changes to the best route:

Note that the White Chuck Road/Trail was destroyed by flooding in 2003, and the Forest Service doesn't intend to repair it: www.fs.usda.gov/recarea/mbs/recarea/?recid=17820

Gerdine Ridge from the North Sauk trailhead now seems to be the most direct route; I'm not sure how much slower it is than the old Sitkum route. [McKeever noted 24 miles for the Sitkum route, vs. O'Rourke's 32 miles for the  Gerdine Ridge route.]