This is a well-developed roadside picnic area along CA-38 east of Redlands. If you are traveling the highway to Forest Falls or Big Bear, Thurman Flats makes a nice stop along the way. It sits above the banks of Mill Creek, a major tributary of the Santa Ana River. During much of year, you can see the creek trickling with storm runoff or snowmelt from the slopes of nearby San Gorgonio Mountain. This is also a great place to spot wildlife, especially birds that favor the streamside vegetation. This canyon serves as a stopover for many species that migrate between North America and South America.
A perfect rest stop for human travelers as well, Thurman Flats features picnic tables, grills, trash cans, and toilets, and there is plenty of space to stretch the legs and relax in the shade. Though the paved picnic area is some distance uphill from the creek, a few short trails lead through the brush and down to the streambed.