North of Seattle and southwest of Mt Vernon, the Skagit River is known as a steelhead fly fishery during Fall and Winter months. Some fishermen do come for the October coho salmon run and the November pink salmon run on odd years.
The Skagit River starts up at Ross Lake in the North Cascades National Park. From Ross Lake, it flows through two dams on the way down to Newhalem. From Newhalem, the Skagit River is free flowing west down to Puget Sound. The section from Newhalem downstream to Marblemount is popular for fly fishing two species of trout on the Skagit River. The Skagit River is part of the 125 mile Skagit Wild And Scenic River System that consists of the Skagit River, the Cascade River, the Sauk River and the Suiattle River.
There is excellent access from SR20 which runs parallel to the Skagit River. The uppermost boat launch for floating the Skagit River is next to Goodell Creek Campground just west of Newhalem.
Note: When fly fishing in the Washington, a valid Washington State fishing license is required in your possession at all times.
Overall, Skagit River is the 8th most popular fly fishing river of all 12 fly fishing spots in Washington.