The East Fork San Jacinto River is a tributary of the San Jacinto River located in Southern California. It flows through the San Jacinto Mountains and is known for its scenic beauty and recreational opportunities, including hiking and fishing. The river's watershed is part of the larger San Jacinto River Basin, which plays a crucial role in the local ecosystem. The river's headwaters originate in the San Bernardino National Forest, where it is fed by snowmelt and rainfall. As it descends, the East Fork meanders through various landscapes, providing habitat for diverse wildlife. Its waters eventually join the main stem of the San Jacinto River, contributing to the region's water supply.