Transport in Montesson is served by buses with T-tickets as well as by several Paris-suburban lines: Line 01, Line 04, Line 07, Line 19, Line 22.
The bus tickets have a category called "Bus T" which is for occasional users and replaces the old tickets in the notebooks of the previous bus network.
The T ticket is also valid on the entire metro (Paris and suburbs) on the RER lines of the RATP and the SNCF. It is sold for a single price of 1.70 € for a journey or 12.50 € for a book of 10. It can be purchased all around the Ile de France metro stations, RER stations, bus terminals, and RATP authorized dealers.
Population
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