A long sandy canyon running north from Borrego Springs into the mountains, with one of the few year-round streams in the park and a string of palm groves along its length. The lower section is open to four-wheel-drive vehicles; further up, the route becomes hiking only. Bighorn sheep, deer and the occasional mountain lion live here, and the canyon is closed to visitors from mid-June to mid-September to give wildlife uninterrupted access to the water.
Three Sisters Falls and the lower palm groves are reachable in a long day hike. The Cahuilla used this corridor for centuries, and bedrock mortars — round hollows worn into rocks by generations of grinding mesquite beans — survive in several spots along the trail.