Oh, brings back a reminisce...
Just a few weeks into my assignment at Kwajalein Island back in 2000, biking to work one day, rode past a construction zone and spied a wheelset by the excavation. I stopped to inspect, looked about 2' gauge, dug up by the crew working on some drainage thing. Rode on to work, and discussed it over coffee with the other fellow who showed up early. He said, "you have to save that thing...", so we got the keys to the stepvan and went to retrieve it before the construction crew arrived. We took it to my quarters, where I set it prominently in the front yard. During the rest of my tour, I cheekily referred to the display as the "Kwajalein Railroad Museum"...
Nearest I could determine, it was a leftover from the narrow gauge setup the Japanese had in the decades of their occupation before WWII. That railway extended from Kwajalein up the east reef for a couple of islands. I think I have a picture somewhere, need to do some basement archaeology to find it...