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Penon Blanco Road (Mariposa County)

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Penon Blanco Road is an approximately 4.5 mile rural one-lane highway located in the Coulterville area of Mariposa County.  This highway is named after the ghost town of Peñón Blanco and was once part of a cutoff from Don Pedro Bar to Big Oak Flat. The Peñón Blanco town site was established near the namesake Peñón Blanco Mine in 1849. The Peñón Blanco Mine extracted hard rock gold ore which would consume the town site during the 1860s.




Part 1; the history of Penon Blanco Road

Penon Blanco Road is named after the early California Gold Rush town of Peñón Blanco. The Peñón Blanco town site was established near the namesake Peñón Blanco Mine in 1849. The Peñón Blanco Mine extracted hard rock gold and would consume the town site during the 1860s. Reportedly the mine had a 20-stamp mill and was actively worked as part of the larger Coulterville mining district until 1912.

Peñón Blanco (shown as Pena Blanca) can be seen northwest of Coulterville on the 1893 USGS map of Sonora. Penon Blanco Road originally served as a cutoff for traffic wishing to bypass Coulterville while traveling from Don Pedro Bar to Big Oak Flat. Penon Blanco Road itself was once continuous with Priest-Coulterville Road.


Penon Blanco Road can be seen as a minor local highway (black line) between California State Routes 132 (now Granite Springs Road) and 49 (red lines) in the Coulterville area west of Blacks Creek on the 1935 Division of Highways map of Mariposa County. 




Part 2; a drive on Penon Blanco Road

Eastbound Penon Blanco Road splits from Granite Springs Road near the Granite Springs Cemetary.


Penon Blanco Road traffic is advised of flood prone terrain 1.5 miles east of Granite Springs Road. 


Penon Blanco Road begins an uphill ascent along the southern flank of Penon Blanco Peak to a vista of Horseshoe Bend in the Lake McClure Reservoir.  

















Penon Blanco Road continues east and intersects Penon Blanco Lookout Road.  This dirt road jogs northward to the top of Penon Blanco Peak (elevation 2,878 feet above sea level). 


Penon Blanco Road makes a steep eastbound descent and terminates at California State Route 49 near Blacks Creek.  The terminus roughly where the town site of Peñón Blanco.


















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