Bonjour, bonnes gens:

Can anyone tell me how difficult it will be (with a moderate amount of luggage) to transfer at St. Michel--Notre Dame from RER B (from CDG) to RER C (toward Gare d'Austerlitz?

Or would a transfer to a Metro line be easier?

Merci bien!

What's "a moderate amount of luggage?"

I'll never go near the MSM RER again with more than a small purse.

I've done it with a roller and carryon, and don't recall any difficulty. IIRC, the C platform is down two escalators from the B.

If you can't get a consensus here, you might consider riding RER B to Luxembourg and transferring to bus N° 89, straight to the train station.

Merci, "incorruptible" Jacobin leader. Although I didn't much like your Reign of Terror, your Paris advice (in this case, about the RER transfer) is tres serviable.

The RER B has escalators everywhere. The RER C is just under the road surface. Not a problem.

(Robespierre has his lines backwards -- the RER B is much deeper because it goes under the Seine.)

I haven't done the transfer recently, but I'd guess that it's easier to do an RER-RER transfer than an RER-Metro transfer because, even though the RATP map shows a connection between RER and Metro (e.g. at St Michel), in reality the metro lines and RER lines are often quite far apart, which means a long underground walk.

On the ratp.fr website, it indicates that the transfer between RER B and RER C should take about 3 minutes to walk, whereas transferring to Metro Line 10 would take 5 minutes.

Thanks to all for the valuable info. We will transfer RER B to C.