Take the route to Honfleur.  Now stay on the road through the center of the city.  You'll pass buy the tourist office and out of Honfleur.  This is actually the D580.  Follow the direction to Le Havre and the Pont de Normandy--the tallest suspension bridge in the world.

Keep on the road that says "circuit de visite" which is specifically designed for bikers and pedestrians to gain access to the bridge.  There is a pretty stretch of road here with  standing willows and cows.

Crossing the bridge is free for cyclists and pedestrians.  It is 5€ for motor vehicles.  Beware of the enormous trucks that pass really close to the unprotected bike route as you sweat up the bridge.

Stop at the top and admire the view!  Here is where the Seine empties into La Manche (the Channel)!

Follow the route down and towards Le Havre by way of the the southern docks.  This road (l'e) offers a great view of the entire bridge.

Signs like these are equivalent to the listing of unlikely ingredients in a chocolate bar in order to protect those with allergies:  i.e. "may contain traces of nuts".  Well, you feel like some nut dust on the long road around the docks with all those monster trucks slamming by, creating sudden explosions of wind that practically topple you off your bike.

Once you enter Le Havre you can go to the center of town or directly to the plages (beach).  This is a good time to stop for a bite!

Return by following the beach to its end (with the sea on your right) where you will see an enormous dock for private boats.  You will eventually get back on the l'e road towards the Pont de Normandy and Honfleur where you might stop for some ice cream before returning to Deauville just in time for a spectacular sunset.