Start at the Ferguson Canyon Trailhead, the trail follows the small creek bed past several climbing crags, crosses the creek multiple times, then at 1.2mi it exists the creek bed left (NW). Take the critical right turn at 1.5mi (otherwise you will end up at an outlook). Continue up the steep scrubby trail as it becomes increasingly less travelled, through a grove of trees at 2.6mi, and encounters a boulder field at 3.4mi. Follow the boulder field SW then S then up the steep forested slope that lead to a saddle.

Stuke Sowle submitted the route:

This route traverses the southern portion of North Cascades National Park. I find it very similar to the Rim to Rim route of Grand Canyon National Park only it is from Pass to Pass. 

The official Howard Watson Nature Trail (http://www.lambtoncountytrails.com/trails/sarnia/Pages/HowardWatson.aspx) is 16 km (10 miles). With the single track on the southwest end, the full length of the trail is 22 km (13.5 miles); extending from the railroad Do Not Enter sign on McGregor Road at the southwest end (Sarnia) to the farm Do Not Enter sign at the northeast end (Camlachie).