El Dorado County is a county located in the U.S. state of California. The county seat is Placerville is and the largest city is El Dorado Hills. The county shares borders with Placer County to the north, the state of Nevada to the east, Alpine County to the southeast, Amador County to the south, and Sacramento County to the west.
El Dorado County is included in the Sacramento-Roseville-Arden-Arcade, CA Metropolitan Statistical Area. It is located in the historic Gold Country in the Sierra Nevada.
The population of El Dorado County has grown as Greater Sacramento has expanded into the region. In the unique Lake Tahoe area of the county, environmental awareness and environmental protection initiatives have grown along with the population since the 1960 Winter Olympics, hosted at Squaw Valley Ski Resort in neighboring Placer County.