Anyone who has taken the RER commuter trains knows of the potential horrors on board - from cramped conditions to a severe lack of air conditioning.
But that's all set to change, at least for the RER E and RER D lines, which serve the suburbs of Paris to the north, east, and south.
France's rail network SNCF announced on Wednesday that it had signed a contract with the Alstom-Bombardier consortium to renew the trains on both commuter lines.
The contract, which will see 255 new trains, is estimated to be valued at €3.75 billion, the biggest ever signed by the region's transport authority STIF.
And the new "boa" trains, which will hit the tracks in 2021, have been designed with the huge commuter traffic levels in mind.
The trains will be entirely open - that is, with no separations between the cars - and will have large doors for "extremely fluid" passenger exits and entrances, Alstom said.
There'll also be three distinct areas on the train: a standing zone for commuters taking short trips, a standing and sitting area similar to a Metro carriage, and a more comfortable seating area for those taking longer trips.
The trains will come with air conditioning and proper access at both ends for those with wheelchairs.
Each of the new trains will be able to carry 1,860 passengers, and will stretch 130 metres in length.
While the plan for now is just for the RER E and D lines, authorities plan to shift 15 percent of the RER A traffic onto the RER E line along the way.
The head of SNCF, Guillaume Pépy, said the move was made to cater for the "ultra dense" traffic usage in the Greater Paris region, which grew at a rate of 7 percent over the last year.
He said that 70 percent of SNCF's passenger traffic comes from the Greater Paris region, even though it only represents 2.2 percent of France's territory.
The RER map below shows the D line in green and the E line in pink.