Which could be a matter of deduction. One place they're not is many of the high, isolated mountain lakes, cut off from migration. Another place is many of the glacially-fed streams too cloudy. With that out of the way, let's look at where the fish are . The wilderness units have several good trout lakes.
Traffic tends to be light to moderate, depending on the season and the lake's isolation.
Some likely candidates include the lower 2 Blum lakes, No Name Lake, Green Lake, Hanging Lake, Kettling Lake, Sandy Lake and Trapper Lake. The Skagit River , Washington's second largest after the Columbia, and its impounded lakes are home to many species of trout and salmon. The Skagit is particularly famous for steelhead. Steelhead fishing is best from February through April. The Stehekin River gives anglers a good chance at rainbow and cutthroat trout.