Center Lake Campground Lower Loop

The Crystal Lake Recreation Area is located in the San Gabriel Mountains of Southern California, administered by the San Gabriel Mountains National Monument (formally the San Gabriel River Ranger District) of the United States Forest Service. The Recreation Area consists of a small lake, an open-air amphitheater, a large public campground containing approximately 120 camp sites grouped into "loops," and a group campground called Deer Flats which consists of approximately 25 camp sites. The Recreation Area contains a United States Forest Service visitor center and a cafe which is open to the public from dawn to dusk except for Tuesdays when the cafe is closed.

Within the Recreation Area are 16 hiking and nature trails which are well-maintained by volunteers who work under the direction of the Forest Service. The Recreation Area is located approximately 26 miles (42 km) north on Hwy. 39 heading out of Azusa, California at the headwaters of the north fork of the San Gabriel River at an elevation approximately 5,539 feet (1,688 m) above sea level.

Crystal Lake is one of only two naturally occurring lakes in the San Gabriel Mountains, the other being Jackson Lake.