This paper presents the development by the Railway Research Centre (CITEF) and the Graphical Engineering Group (GIG) of a simulator based on virtual reality techniques with training aim: a software tool for the simulation of a railway line and a train equipped with the European Railway Traffic Management System (ERTMS) as signalling system. The program takes into account elements as: train characteristics: mass, traction force, etc.; tracks characteristics: curves, gradients, tunnels, electric power supply, etc. and operation characteristics: timetable, route, etc. The simulation system is formed of two main systems: trackside system and trainborne system. The Trackside System includes all information related-to the line, including signalling parameters and assure the security of all the movements. The Trainborne System receives on one side information from the trackside and calculate supervision parameters at the European Vital Computer (EVC), and on the other side considers driver actions on train controls, only if that is allowed by the supervision system. These supervision parameters and circulation conditions are presented to the driver, in ERTMS, at the Man Machine Interface (MMI). Position and velocity of the train must be calculated by this system, too. The user has the option of actually driving each train or using an automatic driver. The driving simulator is connected simultaneously with the visual simulator, which completes the realistic environment that is needed for training. (A) For the covering abstract see ITRD E120189.