A system for automatically announcing the passage of a rail vehicle on a traffic lane of a rail network equipped with a signalling system of the European Rail Traffic Management System type, known as ERTMS, comprising interlocking stations arranged on the rail traffic lane and configured to generate signalling data, said interlocking stations each being connected by a wire link to a control centre of said signalling system, said system comprising the following distinct equipments: - at least one module for listening to and recovering the signalling data carried by each wired link between each interlocking station and the control centre of the signalling system, - a centralised platform for processing the data recovered by each module for recovering signalling data, said platform being configured to generate an alert signal for the passage of a rail vehicle on the basis of said recovered signalling data and data representative of intervention zones on said traffic lane, referred to as intervention data, - at least one device for announcing the passage of a train on the basis of said warning signal generated by said centralised platform, known as a field warning device, arranged in the vicinity of an intervention zone, - a communication network configured to enable each rail vehicle passage warning signal to be transmitted from said centralised platform to each ground warning device, said communication network comprising at least one wireless sub-network accessible by said ground warning devices - at least one multiplexer, referred to as a listening multiplexer, forming said module for listening to and recovering signalling data, said listening multiplexer being adapted to be able to be connected by wire link on the one hand to a concentrator multiplexer connecting said interlocking stations to said control centre and on the other hand to the centralised platform, said listening multiplexer being configured so as to be able to recover said duplicated signalling data within said concentrator multiplexer. - at least one module for listening to and recovering the signalling data carried by each wired link between each interlocking station and the control centre of the signalling system, - a centralised platform for processing the data recovered by each module for recovering signalling data, said platform being configured to generate an alert signal for the passage of a rail vehicle on the basis of said recovered signalling data and data representative of intervention zones on said traffic lane, referred to as intervention data, - at least one device for announcing the passage of a train on the basis of said warning signal generated by said centralised platform, known as a field warning device, arranged in the vicinity of an intervention zone, - a communication network configured to enable each rail vehicle passage warning signal to be transmitted from said centralised platform to each ground warning device, said communication network comprising at least one wireless sub-network accessible by said ground warning devices - at least one multiplexer, referred to as a listening multiplexer, forming said module for listening to and recovering signalling data, said listening multiplexer being adapted to be able to be connected by wire link on the one hand to a concentrator multiplexer connecting said interlocking stations to said control centre and on the other hand to the centralised platform, said listening multiplexer being configured so as to be able to recover said duplicated signalling data within said concentrator multiplexer.