As you can see from the above map, the GO C Paris goes from the Gare de Pont de Rungis, which is listed on the RER C line map as the Pont de Rungis stop. From the train station this shuttle bus service then goes to Terminal 1-2-3 of Orly Airport before then travelling on to Terminal 4 of Orly Airport.
GO C Paris shuttle bus map formats available:
GO C Paris shuttle bus map - PDF (standard quality - 1.168 MB)
GO C Paris shuttle bus map - PDF (high quality - 2.749 MB)
GO C Paris shuttle bus map - Image (standard quality - 1.296 MB)
GO C Paris shuttle bus map - Image (high quality - 2.188 MB)
You may also be pleased to know that GO C Paris runs seven days of the week including on public holidays from 4:43am to 11:16pm at approximately 15 minute intervals, with the departure times for each point listed separately on the timetables.
The RER C line has stops at popular tourist attractions in Paris including the Champ de Mars, Eiffel Tower stop and tickets can be purchased for the GO C bus in conjunction with an RER ticket, which works out slightly cheaper than if buying tickets individually. Just remember that you need a ticket covering Zone 4 to reach Orly Airport, although the Paris Visite ticket covers to Zone 5.
GO C Paris shuttle bus timetables and transport connections