Cedar Mainline (Forest Road 50) is a well-maintained gravel road in the Mount Baker-Snoqualmie National Forest, beginning at its junction with Forest Road 54 (Stampede Pass Road). It travels northwest through dense forest and gently rising terrain before ending at a gated boundary marking the edge of the Cedar River Municipal Watershed. In its final 0.2 miles, the road becomes brushy and overgrown, narrowing very quickly to a point where only single-track vehicles can proceed comfortably. At that point, it transitions seamlessly into Cedar #560 (FS 5060). Along the route, travelers will find a few dispersed campsites and multiple spur roads branching off for further exploration.
Active logging begin in July 2025, resulting in a wide, stable road surface suitable for all vehicle types during dry conditions.