Mount Baker Highway is 35 miles east of Bellingham in northwest Washington. It begins in Glacier and travels east to the road's end at Artist Point. The byway is 24 miles long and follows WA 542, a two-lane paved road suitable for all vehicles. Portions of the byway are subject to closure by snow from November to mid-July.

Mountain Loop Highway is in northwest Washington about 35 miles north of Seattle. The byway follows FSR 20 between Granite Falls and Darrington, a distance of 55 miles. From Granite Falls to Barlow Pass, the byway is a two-lane paved road. From Barlow Pass to the confluence of Sauk and Whitechuck rivers, a distance of 14 miles, the road is primarily a single-lane gravel road. The rest of the byway into Darrington is a two-lane paved road. The roads are suitable for all types of vehicles. Mountain Loop Highway is open year-round from Granite Falls to Silverton; the remaining portion is not maintained in winter.

Mountains to Sound Greenway is in west-central Washington. It follows I-90 between Eastgate, which is just east of Seattle, and Ellensburg. The byway is about 100 miles long and remains open year-round. Use of chains or snow tires are generally required in winter over Snoqualmie Pass.

Sherman Pass is 80 miles northwest of Spokane in northeast Washington. The byway follows WA 20 between Kettle Falls and Republic. Washington Highway 20 is a two-lane paved road suitable for all vehicles. The byway is 40 miles long and is usually open year-round; delays are possible in winter.

Stephen Mather Memorial Parkway is in west-central Washington 40 miles southeast of Seattle. It begins in Enumclaw and travels southeast to Naches. It follows WA 410, a two-lane paved road suitable for all vehicles, and is about 90 miles long. The byway is usually open year-round; temporary closure is possible in winter.

Stevens Pass is in west-central Washington about 40 miles northeast of Seattle. It follows US 2 between Gold Bar and Leavenworth, a distance of 70 miles. US Highway 2 is a two-lane paved road suitable for all types of vehicles. Winter driving conditions in higher elevations require extra caution, otherwise the byway remains open year-round.

White Pass is in west-central Washington about 20 miles northwest of Yakima. It follows US 12, a two-lane paved road suitable for all vehicles, between Naches and Packwood. The byway is 58 miles long and generally remains open year-round. Traveling the byway in winter requires caution, especially in higher elevations.