From Summitpost: Located along the scenic Mountain Loop Highway in the North Cascades, the hike up Mount Forgotten is a nice hike that will take you most of the day. Round trip it is 11.5 miles with almost 4000 feet of gain. It is a Class 3 scramble from the meadows to the summit, loose in spots. The hike starts through a valley with Big Four Mountain at the southern end. In late summer, the area is full of blueberries and huckleberries. The hike over to the summit begins with a loose downclimb and traverses the east side of the summit rocks to a tarn on the NE corner. From there you ascend a gully to the summit. The true summit is the middle of the three points though most stop at the north one. There is some serious exposure over to the true summit.

Other Information
Driving Distance from Portland 270 miles
Driving Time from Portland 5 hours
Expected Duration Car to car in one day
Relevant Books Climbing Washington's Mountains, by Jeff Smoot Cascade Alpine Guide: Stevens Pass to Rainy Pass, by Fred Beckey
Relevant Maps Google map