The traditional area of Place Saint Saveur appears to have been displaced to other areas, French prostitutes appear to have been largely displaced by foreign hookers.
Africans on cours Montalivet (in their vans or big cars), Romanians and Bulgarians on quai de Juillet and la promenade de Madame de Sévigné, the banks of the River Orne in general, or quai Hamelin.
Apparently more hookers are now actually resident in the aream but in the past whores who lived in Paris travelled up to Caen for the day.