Finding French sites that open in March

We are off to France on the 28th Feb and are having trouble finding sites that are open. Our rough route is Calais/Rouen/Chartres/Grezille/Angouleme then down into northern Spain/Portugal...

Can anyone suggest sites near Rouen for our first night? We are staying with friends in Chartres for a few days then carrying on south until we hit the sea :)