State Route 4 (SR 4) is a major highway located in the state of California. It runs approximately 100 miles from the city of Stockton in the south to the city of Marin in the north. The route primarily serves as a connector between various communities and provides access to important regional destinations. The highway passes through diverse landscapes, including urban areas, farmland, and scenic views of the San Francisco Bay. SR 4 is an essential transportation corridor, facilitating both local and long-distance travel for residents and visitors alike. It also intersects with several other major routes, enhancing its significance in the state's transportation network.