After forty years, RER A is renovating between July 23 and August 21. Alternative transportation options are available. Two videos and a website explain the details. The RER A serves forty-six stations (35 RATP metro and 11 SNCF) and carries 308 million travelers a year with two minutes between trains. Read more about the RER A project and other statistics. Guides for How to Get Around this Summer on RER A and C can be downloaded as well as the special instructions booklet, practical guide to prepare ahead, guide for the disabled and how to get around Paris and the outlying areas this summer.....