I am staying at the Bonaparte hotel near St Sulpice Metro. Can you tell me how to get to orly airport from there?
I'm doing this from memory, but you can verify at your hotel or maybe someone will come along who will look it up on the RATP site: take the line 4 metro to Denfert Rochereau. There you have two choices: a bus goes to Orly, or you can take the RER to the Anthony station where you transfer to the Orly shuttle train.
thank you