Back in the end of the 1960s, NATO forces had only 13,000 tanks versus the Warsaw Pact's estimated 42,500. The Red Army tank force was formidable in both number and capability.
So big and powerful, in fact, that some analysts believed that it could have taken over West Germany pretty easily during those days. Thankfully, we could completely destroy each other with nuclear weapons, so nobody really wanted to move their tanks anywhere.
Now, much of the Soviet tank might is now gone. Here is where a whole bunch of them rest, in a tank cemetery in Kiev, Ukraine. [English Russia]