What is the oldest military tank still in service?

Just because technology is old doesn't mean it needs to be retired, as is the case with this particular tank.
eng.belta

‘We use parts of three tanks.’ Stalin's Line museum creates replica of rarest T-34-57

The Stalin’s Line Historical and Cultural Museum is working to restore a rare T-34-57 tank. The running replica of the legendary T-34 is based on the elements of three combat vehicles of the Great ...