The two cars you see here were part of the passenger accommodations on one of two photo freights being operated on the old D&RGW line from Cumbres Pass to Antonito....now part of the Cumbres & Toltec Scenic Railroad. The two freights were making their way eastbound toward Antonito and were scheduled to take the little-used siding at Toltec (basically the middle of nowhere) to allow one of the railroad's passenger trains to pass. A short stock train headed by DRGW Consolidation #315 had just backed on to the siding and our freight, headed by DRGW Mikado #463 was just backing in in front of 315. I had been riding in a rider gondola and had wandered back to the box car (really a concession car with a bar and some restrooms) to retrieve a sandwich that I had stashed there with my gear. As I stood there taking a bite out of my sandwich the train suddenly began to shake and it really caught my attention. I quickly looked to my left out the door of that boxcar that you see, and watched that caboose start swaying back and forth rather vigorously, and then roll over into the ditch beside the track. It all happened very quickly. The train was doing perhaps 3-4 mph. Fortunately, the Conductor, who did not see the caboose roll, sensed that the train was in trouble and shouted STOP(!!!) on the radio. The train stopped in a heartbeat. A couple of the photographers in the caboose quickly took charge of the situation and assessed the condition of the 8-10 occupants. Other than being pretty shaken up, there were no physical injuries. Getting them all out of there took a little doing, but after about 15 minutes, the incident was over. After the passenger train passed, both cars were dropped at the siding, and the photo freights continued on to Antonito.