This is a low-key hike, but a pleasant one nonetheless. If you are looking for additional distance, you can climb to the lookout or hike the Forestry Capital Trail (a separate post) over to McQueen Lake.
To get to Isobel Lake, take the Lac Du Bois Road, then as you near the north end of McQueen Lake, take the fork to your right, following the FSR as it winds past the entrance to the Overnight Center, past Griffin Lake (and the north trailhead to the Community Grasslands Trail), and then as it heads east, take the left fork as it goes over a gentle climb and down to Isobel Lake.
On my visit here in September, the leaves had started to turn colour, the lake was quiet except for pair out in a boat, a fresh hatch was on the lake and fish were jumping, and a few birds called.
(map removed on request)