(A report prepared by the State in the 1880s referred to it as both the "Black Diamond Coal Mining Railroad Company" and the "Black Diamond Railroad.
"[5]) The railroad was built by Gold Rush-era civil engineer and artist Sherman Day, and opened for service in 1868 primarily to serve the Black Diamond Coal Mine at Nortonville.
[5] Trains ran by gravity from Nortonville to Black Diamond Landing because it was all downhill.
Mills and the Black Diamond were transferred to the Bellingham Bay and British Columbia Railroad ("BB&BC") in the state of Washington.
What it looks like on google maps present day [1] The terminus at Nortonville is now a historic preserve managed by the East Bay Regional Park District.