Wikipedia:WikiProject U.S. Roads/Washington/Auto trails
- California-Banff "B" Line, Oregon (Walla Walla) to Idaho (Newport) via PSH 3, PSH 6
- Evergreen National Highway, Canada (Blaine) to Idaho (Clarkston) via PSH 1, PSH 8, PSH 3
- George Washington National Highway, Seattle to Idaho (Coeur d'Alene) via PSH 2
- Glacier Trail, Canada (Blaine) to Idaho (Newport) via PSH 1, PSH 2, PSH 6
- National Park to Park Highway, Oregon (Vancouver) to Idaho (Newport) via PSH 1 (branch on PSH 5, Tacoma-Rainier), PSH 2, PSH 6
- National Parks Highway (Northwest Trail), Oregon (Vancouver) to Idaho (Coeur d'Alene or Rathdrum) via PSH 1 (branch on PSH 5, Tacoma-Rainier), PSH 2
- Okanogan-Cariboo Trail, Wenatchee to Canada (Oroville) via PSH 10
- Pacific Highway, Oregon (Vancouver) to Canada (Blaine) via PSH 1
- Theodore Roosevelt International Highway, Oregon (Walla Walla) to Idaho (Newport) via PSH 3 (Eastern Division), PSH 6
- Yellowstone Trail, Seattle to Idaho (Coeur d'Alene) via PSH 2, PSH 3, PSH 2
- By PSH