For those requiring our coordinates:
Long: @49.3814913 Lat: 3.4314279

From Calais port, get onto the N216

You will be following A26 and N2 to Crouy, and then D925 to Missy-sur-Aisne.

Head east on N216
Continue onto A216 (signs for A26)
Use the left lane to take the exit towards A26/Saint-Omer/Arras, Toll road
Continue onto A26, Toll road. This is the longest part of your journey
Take exit 13 towards Laon/Sissonne, Toll road.
(We recommend stopping off at Laon to stock up on supplies)
At the roundabout, take the 1st exit onto N2/Route Charlemagne
Continue to follow N2, there will be a few roundabouts
Keep right and stay on N2
Take the exit onto D925 towards Missy-sur-Aisne
After a few roundabouts, Turn right onto La Biza
Lac de Missy entrance will be on your left. Drive through and park up on the right.

From Le Harve port, get onto D6015

Continue onto N282
Continue onto A131
Take the exit onto A29/E44 towards Amiens. Partial toll road
Keep right at the fork to stay on A29/E44, follow signs for A151/Dieppe/Amiens/Caiais/Rouen. Toll road
Merge onto A28/E44
Take the E44/A29 exit towards Reims/Lille/Amiens. Toll road
Continue onto A29/E44. Toll road
Take the exit onto A 16/E44 towards Reims/lille/Parisl Amiens-Sud. Toll road
Take the E44/A29 exit towards Reims/Lille/A1/Paris-Est/Amiens-Sud. Toll road
Continue onto A29/E44. Partial toll road
Keep right to stay on A29/E44, follow signs for Paris/Lille/Reims/Saint-Quentin. Partial toll road
Take the exit onto A26/E17 towards Metz/Nancy/lyon/Reims/Saint-Quentin-Centre. Toll road
Take exit 13 towards Laon/Sissonne. Toll road
At the roundabout, take the 1st exit onto Route Chariemagne/N2. Continue to follow N2
At the roundabout, take the 2nd exit and stay on N2 heading to Laon/Soissons/Athies/Laon/Crecy/Serre/Sissonne
Take D925 to La Biza in Missy-sur-Aisne
Turn right onto La Biza