Amtrak's Central Coast Pacific Surfliner, the only train that runs the entire distance of San Diego to San Luis Obispo, is coming out of the Tunnel 28 as it enters the Santa Susana Pass. This train was initiated as an extension of one of the Santa Barbara "San Diegans" in the 1990s, running 350 miles over both Santa Fe and Southern Pacific trackage. The modern version here is passing through a 537' tunnel at MP 443.9. Up ahead, it will hit the longer Tunnel 27 and then the very long Tunnel 26 (aka the "Big Hole").
Stretching from San Luis Obispo to San Diego, the Surf Line has become Amtrak's second busiest route. See the Pacific Surfliner and San Diegan in action along with trains from predecessors Santa Fe and Southern Pacific.