Pinnacle Rock Lookout - 1945
| Registry Numbers | US 1902, CA 97 (view other lookout sites in United States, California) | 
| Date Registered | February 1, 2020 | 
| Nominated by | Brad Eells | 
| Location | 
Mendocino National Forest Lake County, California  | 
            
| Coordinates | 
                            N 39° 08.856' W 122° 45.905' (view using Google Maps) N 39° 08' 51" W 122° 45' 54" N 39.147601° W 122.765086°  | 
            
| Elevation | 4,562 ft (1,390 m) | 
| Built | 1923 | 
| Removed | Unknown | 
| Administered by | US Forest Service - Mendocino National Forest | 
Pinnacle Rock was a California Region 5 Plan 4AR cabin on a short, open timber tower reached by a short stairway up the rock face to the structure.
The lookout was standing and staffed in 1945. Removal date is unknown.