Rohnert Park is a city in Sonoma County, California, United States, located approximately 50 miles (80 km) north of San Francisco. The population at the 2020 United States Census was 44,390. It is an early planned city and is the sister city of Hashimoto in Japan. Sonoma State University, part of the California State University system, is located nearby.

U.S. Route 101 (US 101) is a major north–south United States Numbered Highway, stretching from Los Angeles, California, to Tumwater, Washington. The California portion of US 101 is one of the last remaining and longest U.S. Routes still active in the state, and the longest highway of any kind in California. US 101 was also one of the original national routes established in 1926. Significant portions of US 101 between the Los Angeles area and the San Francisco Bay Area follow El Camino Real, the commemorative route connecting the former Alta California's 21 missions.