For the 35th anniversary of the Prague Metro (or at least some anniversary or another, as I've looked up one source that claims the Metro started operations in 1974), DPP got their oldest Metro train out of storage to do some commemorative runs, and miraculously, it seemed to make it through the day without being trashed, unlike a second-generation train on its recent last run. Being Russian-made, these trains were originally designed for the Moscow Metro, and similar trains can also be seen on the Budapest metro.