Mariposa County is a county in the U.S. state of California. As of the 2010 census, the population was 18,251. The county seat is Mariposa. It is located in the western foothills of the Sierra Nevada mountains, north of Fresno, east of Merced, and southeast of Stockton.The county's eastern section is the central portion of Yosemite National Park.There are no incorporated cities in Mariposa County; however, there are communities recognized as census-designated places for statistical purposes. It also has the distinction of having no permanent traffic lights anywhere in the county.HistoryMariposa County was one of the original counties of California, created at the time of statehood in 1850. While it began as the state's largest county, territory that was once part of Mariposa was ceded over time to form all or part of twelve other counties, including all of Merced, Madera, Fresno, Tulare, Kings, and Kern; and parts of San Benito, Mono, Inyo, San Bernardino, and Los Angeles. Thus, Mariposa County is known as the "Mother of Counties".
