This done yesterday on the last day (Longjumeau - Paris), on the Rue de Versailles coming out of Orsay (48.713463,2.177739).

The Tour is a rather frustrating sport for spectators. If you go to the start or finish of the day's course then you can't get anywhere near the stars because of the security and the spectators. Out on the road you can always find a quiet place where you can get close but they are moving and you only have a clear view for an instant due to the motorbikes escorting them plus the other cyclists.