Crowd of tourists for that small city is a little downside of this city. Of course if you are there in low season then it is normal. So it is not only problem inside the town but parking is problem as well outside.
In summer St Paul falls victim to tourist overload. In common with places such as Brugge and Venice, often you can't see the city for coaches disgorging more tourists.
In addition to an eclectic mix of greying Swedes and Americans, sniffy Parisians and giggling Japanese foursomes , the day I arrived the town was also flooded with Italian youth - around 150 of them - on an "educational trip". As is customary with most teenagers they had little interest in St Paul or in anything educational. Here was a good opportunity for chatting with each other, as they did every day in school , hanging around the toilets in large numbers, photographing each other on mobiles rapidly followed by sqeals of laughter, and shouting excitedly to other friends "Eh Paolo!", " Eh Antonia!" "Que cosa?" "Luigi! Vene! vene!".
Its that "second most visited place in France" bit you can't escape. Try to catch it out of season, or better still, go instead to Haut de Cagnes. Its St Paul without the tourists.
(As an aside, I should say Italian youth are generally very sweet. I had a party of twenty on my plane from London once. They stood in the aisle and chatted compulsively through the whole flight, and returning to their seats for landing, a collective chorus fired up with stilted London Underground announcements "Mind the gap!" "The next station is Picadilly!". "Change at Picadilly, (pause) for the Picadilly line!" Gales of laughter. Then on the final descent, all hands were thrown up in the air , shaking, in a mock roller-coaster dive complete with whoo hoo-ing , followed by wild applause and cheering for the pilot for making a safe landing. I have to say it was very funny.)
The streets and passageways of this village can be treacherous; with cobblestones and inlaid floral patterns, and uneven surfaces, watch your step so as to not ruin your wonderful time with a twisted ankle.
Save the stilletos for evening cocktails, and don those flats!