Revett Lake is located in the Panhandle National Forest about a mile on the Idaho side of the Montana – Idaho border near Thompson Pass (Hwy 471), about 24 miles west of Thompson Falls, Montana. A good dirt road leaves the parking lot at the border and takes you about a mile to the trail head. The trail (Trail #9) is short, a mile and a half to two miles, and it is an easy climb of about a thousand feet to the lake. Despite rather heavy usage on the trail in the summer, no trash at all could be seen along the trail or at the lake and the day I was there I was all alone.
There are good instructions for access to the lake from the Idaho side on the Idaho Panhandle National Forest web site.