San Diego County is home to several rivers, with the most notable being the San Diego River. This river flows approximately 52 miles from the Cuyamaca Mountains to the Pacific Ocean, providing essential water resources for the region. It supports local ecosystems and offers recreational opportunities such as hiking and fishing. Another important river is the Sweetwater River, which runs about 30 miles through the county. It originates in the Cuyamaca Mountains and flows into San Diego Bay. The Sweetwater River is vital for local wildlife and contributes to the area's water supply, making it an important natural resource for residents.