The EN57 is a three-car electric multiple unit built for the Polish State Railways between 1961 and 1993. It was designed for commuter and suburban traffic and therefore has a high number of doors on either side. Each set is composed of a central power car with four traction motors and a control car at each end.
A total of 1,412 were constructed, which have a power of 580, 700 or 1,000 kW depending on construction year. Additionally, 20 were produced as four-car EN71 and 30 EN57 were rebuilt. Many are still operational today with the regional operators. Most of these have been modernised, often with new fronts or even totally new car bodies. 