1 Luxembourg to Châtelet : 1977
2 Châtelet to Gare du Nord : 1981
In 1981, the Ligne de Sceaux was furtherextended to Gare du Nord where it made end-on connection with the rest of RER B.
The old turn-back runnels at Luxembourg reamined out of use until 2001 when they were developed as a two storey underground car park.
3 St Michel Notre Dame : 1988
4 Orlyval : 1994
5 Up to Date : 2016
ILOT every 15 minutes Robinson - Sceaux - Paris - Mitry-Claye
ERIC every 15 minutes Massy Palaiseau - Paris and fast to CDG Airport
EPAF every 15 minutes St Remy - Paris and stopping to CDG Airport
And the network is always busy!