The locomotive you are seeing is an EMD F-7A, one of the most iconic shapes for a locomotive to ever exist. Built between 1949 and 1953, one of the F-unit series of locomotive prime movers, was a common sight on rails around the U.S. Weighing in at over 117 tons and packing an EMD V-16 that displaced 567 cubic inches per cylinder for a combined total of 148.66 liters of diesel power that for decades moved whatever was coupled to it. Nowadays, the existing F-units live the life of museum pieces, but it isn’t a completely easy life. Maintenance is still required and repairs must be made if something breaks down. In this case from 2011, F-7A #913 from the California State Railroad Museum needed repairs, yet there was no direct line from the museum to the Sacramento Locomotive Works shops…which happened to be across a set of Union Pacific tracks. In order to not upset the timetable of the main line, a set of rails had to be erected over the existing rails to move the F-7A across the line. It is impressive that constructing two rails is just enough to move that much weight, and that there are no effects to the main line as a result. Check it out below!
(Thanks to SuperBuickGuy for the tip!)