Mission Trails Regional Park, Nature reserve in San Diego, United States.

Mission Trails Regional Park is a nature reserve spanning over 7,200 acres of mountains, canyons, and grasslands near San Diego. The terrain supports diverse habitats where different plant and animal species thrive throughout the year.

Mission Trails Regional Park was founded in 1974 after San Diego began planning a city park in the 1960s as new housing spread across the area; it took its present name in 1979. The land had been occupied by the Kumeyaay for thousands of years, and more than 30 archaeological sites, including dwellings and spiritual areas, have been studied. Old Mission Dam, finished in 1815, supplied water to Mission San Diego de Alcalá.

Rock art sites within the park show that people have lived and created in this landscape for many generations. These artworks reveal how early inhabitants connected with the land here.

The park has 60 miles of hiking, mountain bike and equestrian trails, plus a rock climbing area and the Kumeyaay Lake Campground with 46 sites beside a small lake. The park is open every day of the year. The Cowles Mountain trail, pronounced "Colz", draws hundreds of people a day to the 1,592-foot summit.

Volunteers began leading "bat walks" in 2022, letting visitors watch and learn about the park's nocturnal animals. San Diego has 23 bat species, and several live in the park, among them the Mexican free-tailed bat, hoary bat, Yuma myotis, canyon bat and Townsend's big-eared bat.