The settlement was established during the California Gold Rush . Mountain Ranch 's post office was established in 1858 . In 1868 , it was moved to another town called El Dorado Camp 1.5 miles south , as there was already an El Dorado post office in California , El Dorado Camp became known as Mountain Ranch . Currently , there are 3 post office buildings in the town . The present one , a small post office which was built in 1956 , and a post office built in 1923 which was once billed as the world 's smallest post office . The original location of the town of Mountain Ranch also has a historical landmark . The bell on the historical marker was used in the local school from 1885 to 1953 . Established as Cave City School District in 1855 , this school joined with the Banner District in 1946 to become the El Dorado Union Elementary School District . In 1942 the last of the gold mines closed . Further economic losses took place in the 1970s , when local saw mills shuttered , and also in 1983 when the Calaveras Cement Co. closed in 1983 . In 2015 , the town was ravaged by the Butte Fire . More than 350 homes along the outskirts burned , but firefighters and local ranchers were able to save most of the downtown
Butte Fire
Butte Fire
Mountain Ranch, California