State Route 142 is a state highway located in the U.S. state of California. It runs through Mendocino County, connecting the towns of Booneville and Navarro. The route is approximately 18 miles long and offers scenic views of the surrounding landscape, including vineyards and forests. The highway serves as an important link for local residents and visitors, providing access to various recreational areas and attractions. It is also a part of the larger network of California State Routes, which facilitate travel throughout the state.