The Odet river goes right by the cathedral and through the old town in Quimper, Brittany. The bridges are absolutely covered in the lushest, most elaborate flower box arrangements throughout all  the historic neighborhoods.
I have written other posts on some of the beautiful and lush planters, borders or roundabouts to be found throughout France, as many small towns compete with one another for the most lavish and sometimes wildly creative floral displays. Here are some of the flowered boxes decorating the town of Daoulas in northwestern France, in particular the small bridges dotting the river.