Union Pacific 4-8-8-4 4014 became the first “Big Boy” steam locomotive to operative under steam over southern California’s Cajon Pass on October 9, 2019! The big engine (recently restored to operating condition, and the largest steam locomotive in the world) is seen descending Cajon Pass at Blue Cut (Swarthout Canyon on the UP). This engine and its train will be making two more crossings of Cajon on October 12 and 13 operating on two fan trips. On this historic day, hundreds of people (and not all of them railfans) witnessed this event, some 78 years in the making.