The Big Morongo Canyon Preserve is a 31,000 acres (130 km2) native plants habitat and wildlife preserve located in the Little San Bernardino Mountains of the Transverse Ranges, in the transition zone between the higher Mojave Desert and lower elevation Colorado Desert section of the Sonoran Desert. Due to its location within this transition zone, the area is especially high in natural diversity. The natural spring fed desert oasis found here is one of the 10 largest Cottonwood (Populus fremontii) and Willow (Salix lasiolepis) riparian habitats in California. It is also identified by the Audubon Society as one of the most important avian habitat areas in California.
The entrance to the preserve is located within Morongo Valley, California an unincorporated town within San Bernardino County, California just off California State Route 62. Admission is free. The preserve is open from 7:30 am to sunset, each day.
The last people to inhabit the canyon before the arrival of white settlers were the Morongos, a powerful clan of Serrano Indians. They lived peacefully in this canyon and surrounding valley until the mid-1800s.
The preserve was the site of a large (>10 acre) historic “Maringa” (Morongo) Native American Serrano permanent settlement. The site, CA SBR‐561, is a large residential site with a continuous, dependable source of water. The valuable biotic resource assemblage that the water attracted, provided for ample food and manufacturing materials to support the view of it being a permanent Maringa Serrano residence for a long span of time. Present on the site are bedrock mortars, several types of ceramic wares, lithic tool stone debitage and numerous late period projectile points.