 California State Route 70 crosses over Beckwourth Pass and the Feather River Route of the former Western Pacific, now Union Pacific Railroad beneath it via the Chilcoot Tunnel.Route 70 and the railroad line provide an alternate route between Sacramento, California and Reno, Nevada when Interstate 80 and the Overland Route, which cross the Sierra Nevada near Donner Pass, are impassable due to winter storms.James Beckwourth is credited with the discovery of Beckwourth Pass in 1850.