Ralph B. Clark Regional Park - Perimeter Trail Professional Review and Guide
"Located in the northwest corner of Orange County on the Buena Park/Fullerton border, this park owes its origin to our fascination with fossils. It seems 12,000 years or so ago, the ring-tailed cat, ground sloth, and ancient mammoth roamed a region of meadows, marshes and woodlands, an environment altogether different from present-day Orange County. Extensive fossil beds were discovered when sand and gravel was excavated during the 1950s and 1960s for construction of the Santa Ana and Riverside freeways by the California Division of Highways (now Caltrans). Paleontologists identified the remains of prehistoric whales, bison and even a camel. By public demand, Emery Borrow Pit, as the excavation site was known, was purchased by Orange County in 1974, and opened as Los Coyotes Regional Park in 1981. It was later renamed for Ralph B. Clark, a county supervisor who retired in 1987 after 16 years of public service and was devoted to the creation of this 105-acre park."