This past month I drove Redinger Lake Road (Madera County Road 235) while on my way to see the Italian Bar Bridge. Redinger Lake Road is a curvy 8.6 mile road which connects Powerhouse Road (Road 222) east to Italian Bar Road (Road 225). What makes Redinger Lake Road interesting is that it was a haul road completed in 1950 for the construction of Redinger Dam (Big Creek Dam #7). There doesn't appear to really have been any work done on Redinger Lake Road since it was completed as it more or less stands as a testament to when building hydroelectric infrastructure on the San Joaquin River was at it's peak.
https://www.gribblenation.org/2019/10/redinger-lake-road-road-235.html