Having received a private tour from Mr. Cossey of some of the Colombian railways I can certainly attest to the fact that he knows his stuff when it comes to the culture and history of the country. Colombia is beautiful place and is not the same country that I think Americans still stereotype it as. As far as the railroads go they are almost exclusively 36" (not meter) gauge. They are a fascinating mix of modern with diesels - some as new built as 2015 - and concrete ties and steam still maintained in historic shops. The Bogata tourist train is awesome and the FDP railway on the west in Cali has grades and curves that rivals, and exceeds, the C&TS and D&SNG. That all said Colombia's railways seem to be always in state of flux so visit while you can.