For fares information :
http://www.ratp.info/touristes/index...ts&page=tarifs
Orlybus
Traject: Orly <-> Paris Denfert-Rochereau
Price: 6.40 EUR
Time: 30mins
Frequency: 30mins
Orlyval
Traject : Orly <-> Antony / Orly <-> Paris (Orlyval + RER B)
Price: 7.60 EUR / 9.85 EUR (to/from Paris)
Time: 7mins (Orlyval) + 25mins (RER B)
Frequency: every 7mins
RER C
Traject: Aéroport d'Orly <-> Paris
Price: 3.7 EUR (+2 EUR for Shuttle Terminals <-> RER station)
Time: 25 mins (Aéroport d'Orly - Austerlitz)
Frequency: a train every 20mins