Turnbull Canyon is a 4-mile loop trail located near Whittier, California, and is part of Puente Hills Preserve. It lies in the northern-central part of the preserve, and is an east–west canyon with relatively steep drainage. The canyon has a creek at its bottom that supports a narrow strip of riparian woodland dominated by sycamore trees, while the slopes are covered in coastal sage and native and non-native grasses.