Cajon Pass (Summit)

Cajon Pass Summit is a pilgrimage for serious railfans — one of the few places in North America where you can watch two Class I railroads operate four main tracks through a steep mountain corridor, all from public viewpoints within yards of the ballast. Access is via Forest Service roads that parallel the right-of-way off California Highway 138 and Summit Valley Road. From various pullouts, you can stand close enough to feel the ground shake as trains grind upgrade at 14 to 22 mph or descend using dynamic brakes at 20 to 30 mph.

The iconic viewing spot is Hill 582, an unofficial railfan overlook named for its USGS elevation contour. Maintained by volunteers who planted shade trees and installed benches, Hill 582 provides commanding views of all three BNSF main tracks and UP's Palmdale Cutoff simultaneously. On a good day, you can spot approaching headlights miles away, giving ample setup time. Expect mostly GE ES44C4s and EMD SD70ACes leading trains that routinely stretch beyond 10,000 feet. BNSF ended regular manned helper service in October 2009, switching to distributed power, though UP still maintains one helper pool.

Note that Summit itself is fenced, lit, and guarded by security. BNSF's Citizens for Rail Security program means private security patrols the area regularly. Stay on public Forest Service roads and respect railroad property boundaries. A high-clearance vehicle is recommended for reaching Hill 582 via the dirt access roads.

Summit sits at 3,777 feet elevation (reduced from 3,829 feet after AT&SF's 1972 realignment project that also eased curves from 10 to 4 degrees) at the transition between chaparral-covered slopes and high-desert scrub. The pass was carved by the San Andreas Fault, which runs directly through the area — Mormon Rocks, a striking white sandstone formation visible from Highway 138, marks the fault zone.

Joshua trees and scattered pinyon pine frame rail shots against tawny ridges. In winter, the peaks of the San Gabriel Mountains carry snow, adding contrast to the desert foreground. Visibility often exceeds 50 miles on clear days, though summer afternoons bring heat haze that distorts telephoto shots. The pass is notorious for wind — Santa Ana season (October through November) can bring gusts exceeding 60 mph, strong enough to topple trucks on nearby I-15. The area sits within the San Bernardino National Forest, a 676,000-acre preserve established in 1907. Spring and autumn offer the most comfortable shooting conditions with crisp light and moderate temperatures.

The original single-track Santa Fe line opened through Cajon Pass in 1885, effectively linking Los Angeles with the rest of the United States. A second track followed in 1913 to handle booming citrus and oil traffic. Southern Pacific (now UP) completed its Palmdale Cutoff in 1967, giving SP a lower-grade route to the ports and introducing competitive drama still felt today. BNSF’s 2008 third mainline project at Summit eliminated a decades-old bottleneck and stands as one of the largest recent capacity upgrades in U.S. mountain railroading. Artifacts of earlier eras—abandoned telegraph poles, concrete mileposts, and foundation remnants of helper-station cabins—dot the hillsides, silently narrating 140 years of rail history.

Cajon Pass is widely regarded as the busiest railroad mountain crossing in the United States. With BNSF's $90-million third main track (completed November 3, 2008, adding nearly 16 miles of track and increasing theoretical capacity from 100 to 150 trains per day), the pass handles an extraordinary volume and variety of traffic. Few locations offer simultaneous views of four main tracks operated by two competing Class I railroads.

The accessibility sets Cajon apart — public Forest Service roads and Highway 138 viewpoints bring you within arm's reach of mainline action, unlike many remote mountain passes that require long hikes. The constant flow (a train roughly every 10-15 minutes during peak periods) means minimal downtime. The mix includes double-stack intermodal, manifest freight, autoracks, unit grain and oil trains, and Amtrak's Southwest Chief — providing variety that keeps every hour interesting.

The pass is also evolving: Brightline West high-speed rail is under construction through Cajon Pass as part of the Las Vegas to Rancho Cucamonga route following the I-15 corridor, adding another chapter to over 140 years of railroading history through this gap in the mountains.