From Concrete or nearby Baker Lake, the Pacific Northwest Trail heads through low-lying forests as it makes its way to Anacortes and the Puget Sound. The Forest Service did substantial work in 2015 clearing out the overgrown Forest Service roads west of Concrete, and at times thru-hikers were diverted to other roads to avoid the brush-clearing work. Another option that many thru-hikers take from Concrete is to follow the old railroad that has been converted to a rails-to-trails route that runs alongside Highway 20 and goes through Sedro-Woolley, the home of the Pacific Northwest Trail Association.
This section of the trail is what is sometimes referred to as a zone of connection. Various trails, Forest Service roads, and paved roads are linked together to create a route to connect the Cascades to the coast. While the trail requires sections like this one for it to work, few people choose to use this area for hiking. This means the routes are usually more confusing, and it is unlikely you'll encounter many campgrounds or well established trails on this part of the trip. But the route also continues through pastoral landscapes and is routed in a way to make the travel as interesting as possible.
After crossing under I-5 the trail wends its way up Chuckanut Mountain and provides stunning views of the Puget Sound and the San Juan Islands. Chuckanut Mountain stands some 2,000 feet above Samish Bay, a few miles to the northeast of Anacortes. After descending from this small section of trail the route returns to hardscape, following Chuckanut Drive into Edison, Washington, and then continuing on Edison Road around Padilla Bay. To walk to Anacortes, the office trail route follows Highway 20 for a few miles and then diverts onto March Point Road and across a bridge into town. The route planners have done a good job keeping as much of the PNT on a trail as is possible in this section, but be prepared for a lot of road walking as well. Entering the San Juan Islands is an interesting change and provides a much more urban feel than what thru-hikers have experienced on any other section of the PNT. For some it's a welcome change, while for others this area is one to pass through with some high-mileage days as quickly as possible.
Anacortes is a large town with an active shipping port and an industrial character. The town has all of the services thru-hikers need to fully resupply, but given the number of small towns that the route intersects with in the next few days before reaching Port Townsend, picking up just a day or two of supplies is more than enough. Finding a place to sleep in Anacortes is the bigger challenge. Washington Park, at the western edge of the island, has a large campground that suits thru-hikers wishing to avoid paying for a room for the night.
For additional details, refer to the following PNT sections: