This month’s question was where was the first discovery of gold in commercial quantities made? The first such discovery was made in 1842 by Francisco López at Placerita Canyon. Placerita Canyon is about 4 miles east of Newhall in the San Fernando Hills.
The question (& answer) were taken from p. 159 of
Historic Spots in California by Hoover, Rensch, et al. The book was published in 1990 by Stanford University Press.