MP: .03
Location: US-12 and Silver Creek Rd, Silver Creek, Lewis Cty
Reassurance shield at the beginning of the route
MP: 1.88
Location: Harmony Rd and Cinebar Rd, Lewis Cty
Bear right to stay on SR 122 east, straight on Cinebar Rd heads up to Cinebar and SR 508
MP: 4.11
Location: Harmony Rd and Ike Kinswa State Park Rd, Lewis Cty
Reassurance shield after passing the Ike Kinswa State Park. This state route only exists as a state route to directly connect US-12 and the rest of the state route system to the state park.
MP: 7.76
Location: Harmony Rd and US-12, Mossyrock
SR 122 returns to US-12 to terminate as quickly as it begins
MP: 7.88
Location: US-12 and Harmony Rd, Mossyrock
Turn left for 12 west, right for 12 east to I-5
