An eastbound intermodal train out of Lathrop, CA, heads into the heart of the Feather River Canyon. Slide fences in this part of the canyon don't keep rocks off the right of way, but rather, when a rock breaks one of the wires, a signal goes" red," stopping an approaching train from running into a slide. Rocks slides are common in the Canyon, especially when it's raining or there's snow run-off.