Washington 409
| Termini | WA-4 in Cathlamet to the Puget Island ferry landing |
| Length | 3.8 miles |
| "Where does it go?" | WA-409 runs from Cathlamet south to Puget Island in the Columbia River. WA-409 ends at the Puget Island ferry landing. |

Highways of Washington State - State Route 409
Washington
State Legislative Code - Route 409