We've had recently an abandoned railway in Abkhazia, abandoned as a result of USSR collapse when new "independent" republics couldn't maintain the complicated and high-cost USSR legacy objects. But this one was abandoned long before the USSR collapse, it was doomed to be abandoned from the beginning. It was built by a personal Stalin's order
in the middle of nowhere - deep inside Northern Siberia between Salekhard city and Igarka town. It was not connected with any other Russian Federal Railway System and the purpose of it still is not very clear, so as a senseless toy it way abandoned pretty soon and now rusts accessible only with a helicopter.