The Pacific Northwest Trail (PNT) is a 1,200 mile, 1,900 km hiking trail which traversed the northernmost area of the United States from the Continental Divide in Montana to the Pacific Ocean on the Olympic Coast of Washington. Along the way, the PNT crosses three national parks, seven national forests, and two other national scenic trails. It travels against the grain of several mountain ranges, including the Continental Divide, Whitefish Divide, Purcells, Selkirks, Kettles, Cascades, and Olympics.

In 1977, the Pacific Northwest Trail Association was founded by Ron Strickland to maintain and advocate the PNT. This same year, the first five successful thru-hikes of the Pacific Northwest Trail were completed.

In 1984, the first full length guide book was published.

It was designated as the Pacific Northwest National Scenic Trail by Congress in 2009.

At the eastern terminusat Chief Mountain Customs on the United States–Canada border in northwest Montana, the Pacific Northwest Trail traverses the high mountains and valleys of Glacier National Park, where it shares mileage with the Continental Divide Trail. Then it enters Flathead National Forest, travels across the Flathead River into Polebridge, Montana, up the Whitefish Divide, into Kootenai National Forest, and through the Ten Lakes Wilderness Study Area on its way to the Idaho state line.

In Idaho Panhandle National Forest, the PNT crosses the Moyie River Valley, winds its way through the forest lands, dikes, and farmlands of the Kootenai River Valley, up Parker Ridge to the Selkirk Crest, then down Lions Head and over Lookout Mountain to Upper Priest Lake. From there, the trail climbs toward the Washington state line. Next, the trail wends along the Kettle Crest, through Okanogan-Wenatchee National Forest and into the range lands and orchards of the Okanogan River Valley. From the city of Oroville, Washington, the PNT follows the Similkameen River to Palmer Lake, where the trail travels through Loomis State Forest, and then begins its ascent into the Pasayten Wilderness, where the PNT shares tread with the Pacific Crest Trail.

Along the dikes and through the farmlands of Skagit County, the trail traverses Fidalgo Island, crosses the bridge at Deception Pass State Park and continues across Whidbey Island to the Washington State Ferry Terminal in Coupeville, Washington. After a thirty-minute ferry ride, the trail picks up in the seaside community of Port Townsend, Washington and the confluence of three trails: the Larry Scott Trail, the Olympic Discovery Trail, and the Pacific Northwest Trail. The trails circumnavigate the northeastern tip of the Olympic Peninsula and Discovery Bay before going their separate directions, with the PNT turning southwest through Olympic National Forest, Buckhorn Wilderness and into Olympic National Park.

As the trail leaves the park and travels along the Bogachiel River it finds its way through the northern end of the Hoh Rain Forest to the Pacific Ocean at the mouth of the Hoh River. There, the trail turns north and wends along the wilderness coast where it enters the Quileute Indian Reservation near the town of La Push, then continues north to its western terminus at Cape Alava.