Forbes Mill Museum

Forbes Mill Museum, housed in a two-story building of the original 1854 flour mill, offers a glimpse into Los Gatos' history. Built by James Alexander Forbes as California's first commercial flour mill, over the years, it served various roles, including a power plant and a PG&E substation. Saved from demolition in 1982, the building now features historical exhibits as part of New Museum Los Gatos.

Forbes Mill is a former flour mill built in 1854 as the first commercial building to be established in what was first called Forbes Mill, then Forbestown, and finally Los Gatos. It served as the Los Gatos History Museum, saved from destruction in 1982. The museum seems open on weekends; its collections are part of New Museum Los Gatos. The building is owned by the City.
The existing two-story building is actually a storage annex which was added to the original four-story stone mill building in the fall of 1880.

It was built as the Santa Rosa Flour Mill by James Alexander Forbes, born in Scotland in 1805. He came to California in 1831 as British Vice-Consul in San Francisco.
The California Gold Rush inspired James to build the first flour mill, with prices of $50/barrel. In 1850 he purchased 2,000 acres (8.1 km2) on Los Gatos Creek. In 1853 he raised $130,000 for construction from two lenders. The milling machinery arrived from New York around Cape Horn, the mill started grinding flour on December 1, 1855.
Unfortunately, Forbes’s dam carried water via a flume from 0.5 miles (0.8 km) upstream to two 20-foot (6.1 m) high water wheels which proved to be inefficient, so he had to keep raising the water level, only sufficient during the winter months. Meanwhile new mills and the waning Gold Rush drove flour prices down to $5/barrel.
The mill and land were sold in 1857 to Gustave Touchard, one of Forbes’ creditors. Touchard hired others to run the mill, but they did not have much success with it either.
In 1866, he sold the mill to William H. Rogers, who had worked at a flour mill in Detroit and his own Mountain Flourmills in Placerville. He served as postmaster of Placerville and sheriff of El Dorado County until his purchase of now-named "Clifton Mill". He raised the waterhead to 65 feet (19.8 m), then 200 feet (61.0 m), replaced the water wheels with turbine wheels, upgraded machinery, and constructed reservoirs for year-round production of a profitable 100 barrels of flour a day.
In 1887 it became a power plant for the Los Gatos Ice and Power Company, a brewing and bottling company, the Los Gatos Gas Company, and finally the PG&E substation. The original "Santa Rosa" Flour Mill building was torn down in 1916. The mill remained a storehouse for PG&E until after World War II. It was abandoned and finally in 1971 revived as a youth center with live rock music weekends.

en.wikipedia.org/wiki/Forbes_Mill
nps.gov/nr/travel/santaclara/for.htm