O'Neill Regional Park

O'Neill Regional Park is a major regional park and greenway in eastern Orange County, California, United States, located along Trabuco Creek and Live Oak Canyon. The park encompasses 4,500 acres (1,800 ha) of canyon and riparian zone habitat, and includes campgrounds and trails for hiking, biking and horseback riding.

The park was first established in 1948 when the owners of the O'Neill Ranch donated 278 acres (113 ha) of land for recreation purposes. Numerous land acquisitions between 1948 and 1982 brought the park to its present size. Many flora and fauna can be sighted, such as poison oak, bobcats and mountain lions, which are very rare. The Acjachemen village site of Alume is located within the park's area.