"In Nevada County northwest of Nevada City and east of the junction of the North and Middle forks of Yuba River. Gold was not discovered here until January, 1853. One of the earliest claimants, Christian Kientz, a Mexican War veteran, saw in the hill above his claim a resemblance to the elevation at the entrance of Santa Cruz harbor, San Juan de Ulloa, and named it accordingly. In the spring of 1854 the Middle Yuba Canal brought water, and the camp enjoyed a fair prosperity. On May 21, 1857, a post office was established with the adjective "north" added to the name to distinguish it from San Juan in Monterey, later San Benito County. It has been claimed that hydraulic mining really started here. In 1858 the poet Benjamin Parke Avery, after years of unsuccessful mining, bought the newspaper and published it as Hydraulic Press. A decade of great prosperity began August 5, 1859, when the completion of the 300-mile-long flume from the lakes around present Bowman Lake was celebrated. The population of the town reached several thousands at times. It is one of the few gold towns that enjoyed a respectable library. The North San Juan Ridge along the ancient channel of the Yuba River was probably the richest hydraulic mining region in the state."

Erwin G. Gudde, 1975