Provins is actually 1h24 from Paris - rather a long journey compared to the places I listed)
Clearly being a fan of the Line 4 diesels out of Est (:cry
Provins used to be top of my list but (however bonkers this sounds!) I omitted it because now, being a modern plastic unit train and a long way from Paris I was giving other places precedence.
Rambouillet probably stands out (especially to fans of 'proper' trains) as the best remaining option, as it has trains to Paris that are are loco and coaches (ironic given that when I did it the Ile de France trains were unit (although there were BB9200 on trains from further afield that called at Rambouillet).
Sadly there are a few larger nice places that suffer a double whammy - they fall outside the Ile de France ticketing area, and are the also first stops after Paris on loco hauled expresses (Chateau Thierry, Sens, Montargis, Creil etc) so you can't for instance get the BB15000 on the Est Bar le Duc route or the hauled trains from Dijon.
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