The Colton Crossing was an "at grade" railway crossing situated in Colton, California, directly south of Interstate 10. First built in 1883, it was the site of one of the most intense Frog wars in railroad construction history, leading to a personal confrontation between famed lawman Virgil Earp and California Governor Robert Waterman. The crossing was the intersection of the tracks of the BNSF and Union Pacific (UP) railroads. Union Pacific track ran east-west at the crossing while the BNSF track ran north-south. Metrolink trains and Amtrak's Southwest Chief also used the BNSF track through the crossing while Amtrak's Sunset Limited used the UP tracks. The Union Pacific track comes from the east through the Coachella Valley and into the yard in West Colton. The BNSF track from the south continues through the yard in San Bernardino and north to Cajon Pass.
Construction of the California Southern Railroad, a subsidiary of Atchison, Topeka and Santa Fe Railway (now BNSF Railway), was repeatedly interrupted by Santa Fe's rival, Southern Pacific Railroad (SP). In one instance, California Southern was set to build a level junction across SP tracks in Colton. California Southern engineer Fred T. Perris ordered the crossing built and acquired the track section for the railroad. When the track was delivered to National City in July 1883, SP officials hired the sheriff there to seize the track section and prevent its installation. The sheriff kept the track under 24-hour guard, but Perris's men were able to retake the track while the sheriff napped, loaded the track on a flatcar and started northward with it toward Colton, where it was to be installed.
Perris obtained a court order on August 11, 1883, that would legally allow California Southern to install the new track section.
I thought it advisable to have final order of court printed and each SP employee served. It was also asserted that headquarters at San Francisco had not received the final order. The danger of a riot was so imminent, by legal advice I had the order telegraphed to the Sheriff at SF to serve on the President or Secy. ... In the meantime the Sheriff [in Colton] had organized a posse, with arms and was waiting for order of court to clear the track, on our application.:133
Perris' crew was ready to install it as soon as SP's Overland Mail passed the point of intersection between the two railroads. However, at that moment an SP locomotive arrived at the scene pulling a single gondola and stopped. The engineer of the SP locomotive then drove the train back and forth slowly at the crossing point in an effort to prevent the California Southern crew from installing the crossing. Southern Pacific had hired the famed lawman Virgil Earp to guard its tracks in Colton and he rode in the cab.
The citizens of Colton supported Southern Pacific, but Southern Pacific had bypassed nearby San Bernardino, upsetting the residents. They hoped the California Southern line would put their city back on the map. On the morning of September 13, events reached a head in a confrontation that was quickly dubbed the "Battle of the Crossing". Citizens from Colton and San Bernardino gathered on either side of the tracks—San Bernardino residents on the north and the citizens from Colton on the south—with the Southern Pacific locomotive between them. Men on both sides carried picks, shovels, shotguns and revolvers. Virgil Earp stood in the gangway between cab and tender facing the San Bernardino mob, his revolver in hand. It was believed that the gondola held a number of SP men with rifles and other weapons who crouched below the walls of the car so as not to be seen.:27
Governor of California Robert Waterman ordered San Bernardino County Sheriff J.B. Burkhart to enforce the court order. Burkhart deputized 10 dependable men and personally escorted the governor to the crossing site. Waterman stood between the SP locomotive and the San Bernardino mob and read the court order. The governor said the locomotive must be cleared away at once. He told Virgil Earp that if he made any move with his six-shooter, Burkhart and his deputies were authorized to shoot. The tension between the crowds, lawmen, and governor made a gun fight likely—perhaps bloodier than his Tombstone shootout. Earp realized that further resistance was hopeless and would lead to bloodshed. He holstered his weapon and ordered the engineer to move the locomotive.
The track was cleared and the crossing was installed. The first train from San Diego arrived in Colton on August 21, 1882 (before the crossing was installed), and the first train to San Bernardino arrived on September 13, 1883.
Grade Separation and Flyover
Colton Crossing's proximity to two major rail lines in Southern California led it to become a site of heavy rail traffic. More than 110 trains used the right-angle at-grade rail crossing each day, which, until the flyover project was completed, had been a significant cause of congestion on the main lines of UP and BNSF.
In December 2006, the Alameda Corridor Transit Authority (ACTA) presented a feasibility study to analyze alternatives and costs for design and construction of an east-west structure, which would grade separate both BNSF and UP main line tracks at Colton Crossing. In addition, ACTA prepared a report on a proposed north-south flyover to the south of Colton Crossing to reduce train crossing conflicts and hours-long congestion. The report was evaluated by ACTA, UP, BNSF and the San Bernardino Associated Governments (SANBAG). SANBAG conducted community outreach meetings to assist the project team with selecting the final build option. In November 2011, work began on the grade separation project, with the final design being a 2.2-km east-west flyover of Union Pacific tracks over north-south BNSF tracks. Work was initially expected to take four years at a projected cost of $202 million. Skanska was the lead contractor on this project.
The Colton Crossing flyover project was completed in August 2013. Innovative construction methods including cellular embankments as well as low bid prices were responsible for the project coming in eight months ahead of schedule and significantly under budget, with the final cost being $93m versus the budgeted $202m. The completion of the project has resulted in greatly reduced congestion, leading to reduced travel times, a 31,000-ton drop in annual greenhouse gas emissions, and $241m saved in time spent traveling. 
- Waters, Leslie L. (1950). Steel Trails to Santa Fe. Lawrence, Kansas: University of Kansas Press.
- "Frontier Lawman Virgil Earp". June 12, 2006. Retrieved 9 May 2011.
- Duke, Donald; Kistler, Stan (1963). Santa Fe ...Steel Rails Through California. San Marino, California: Golden West Books. ISBN 0-87095-009-6.
- Signor, p 17.
- "Colton Crossing grade separation gets underway". Railway Gazette. November 25, 2011. Retrieved August 29, 2013.
- ACTA Colton Crossing Feasibility Study
-  SANBAG Colton Crossing web site
- "Colton Crossing grade separation completed". Railway Gazette. August 29, 2013.