The San Luis Rey River Valley is located in northern San Diego County, California. It is named after the San Luis Rey River, which flows through the valley and eventually empties into the Pacific Ocean. The area is characterized by its scenic landscapes, including rolling hills, agricultural fields, and a variety of wildlife habitats. The valley is home to several communities, including Oceanside and Fallbrook. It is known for its rich agricultural history, producing crops such as avocados, citrus fruits, and flowers. The region also features recreational opportunities, including hiking and biking trails along the river and surrounding areas.