Christos K.
Google
Entrance to this enchanting little museum is hidden inside the main Piraeus train station. The museum is privately owned but charges no entrance fee. It is run by enthusiast and ex-employes of the electric railway company.
It is a shame that the museum forbids photographs as I think they might help tempt people to take a look.
I found the museum fascinating, and despite being small, you can easily spend a an hour or two there.
The museum charts the development of the Athens Piraeus public transport system from horse drawn tram through to the electric train. There are over 6000 exhibits, everything from tickets, to switch gear, signalling equipment, rail laying and cutting equipment, photographs and models. There is even a loving restored wooden carriage. One of the best little museums I have stumbled upon!