California's 48th congressional district is a congressional district in the U.S. state of California based in San Diego County in Southern California as well as Murrieta and Temecula in southwestern Riverside County. It is currently represented by Republican Darrell Issa.

Murrieta is a city in southwestern Riverside County, California, United States. The population of Murrieta was 110,949 as of the 2020 census. Murrieta experienced a 133.7% population increase between 2000 and 2010, making Murrieta one of the fastest-growing cities in the state during that period. Largely residential in character, Murrieta is typically characterized as a bedroom community. Murrieta is bordered by the city of Temecula to the south, the cities of Menifee and Wildomar to the north, and the unincorporated community of French Valley to the east. Murrieta is located in the center of the Los Angeles-San Diego mega-region. Murrieta is named for Juan Murrieta, a Californio ranchero who founded the town.