Air France shuttle buses (Les Cars Air France) run from Paris-Orly Airport to central Paris seven days a week.

There are Métro stations and taxi stands at each of the central Paris airport bus stops, allowing you to continue the journey to your hotel or apartment as you wish.

Route 1 & 1*: Orly-Gare Montparnasse-Invalides
Route 1 buses connect Paris-Orly Airport's Orly Sud (Sortie/Exit L) and Orly Ouest (Sortie/Exit H) terminals with Gare Montparnasse and Hôtel des Invalides in central Paris.

Route 1* (that's 1-star) buses connect Paris-Orly Airport's Orly Sud (Sortie/Exit L) and Orly Ouest (Sortie/Exit H) terminals with Gare Montparnasse and Place Charles de Gaulle-Étoile.

Buses depart the airport every 30 minutes from 06:15 am to 23:15 (11:15 pm).

The journey takes about 35 to 50 minutes (depending on traffic) and costs 10€ (half price for kids).

Route 3: Roissy CDG-Orly Airport
Route 3 buses connect Paris's two principal airports, traveling from Paris-Charles de Gaulle Airport to Paris-Orly Airport every 30 minutes from 05:55 am to 22:25 (10:25 pm); and from Orly to CDG from 06:30 am to 22:30 (10:30 pm).

The fare is 18€ (half price for kids).

Alternatives
The OrlyBus, operated by RATP, Paris's city bus company, connects Paris-Orly Airport with Place Denfert-Rochereau and the Denfert-Rochereau Métro and RER suburban train station in southern Paris. More...

The OrlyVal tram and RER suburban trains will take you to central Paris most quickly and inexpensively. More...

An airport shuttle service is another good way to go. More...