Great Valley Grasslands State Park preserves a rare remnant of native valley grassland in California's San Joaquin Valley, part of a landscape once widespread across the Central Valley. Established in 1982 from the former San Luis Island and Fremont Ford State Recreation Area, the 2,826-acre park lies within the larger Grasslands Ecological Area, where managed wetlands and grasslands support diverse wildlife. Its seasonal appeal includes spring wildflowers, fishing, and wildlife watching. The park protects native plants, endangered herbs, rare invertebrates, giant garter snakes, California tiger salamanders, and wintering waterbirds, making it both a recreation area and an important refuge for a much-altered ecosystem.