Use a roundabout in France and, depending on the age of French driver, you'll find out if they use the 'new' rule of traffic on the roundabout having priority or the 'old' rule where the driver entering the roundabout has priority - crunch!!
You have the right of way at Rounabouts unless otherwise directed, Hemel Hemstead is another issue, you have ONE large roundabout & if I can remember right, there are either six or eight mini rounabout's going off that.