Placer County is located in the Sierra Nevada of the U.S. state of California, in what is known as the Gold Country. It is one of the fastest growing counties in the state. It is also considered one of the more politically and morally conservative counties and has less ethnic diversity than in other regions of California. The county seat is Auburn. In 2004, the population had grown to 307,004. Placer County was created in 1851 and derived its name from the places where the method of extracting gold from the earth, called placer mining, was practiced. The county has a total area of 1503 mi², 93% of it is land and 7% of it is water.