When you're planning your visit to Le J, you could take public transportation to the station Transunivers Voyage, which is the nearest station at 730 meters distance to the restaurant.
As soon as we have a menu for Le J from Ambares-et-La Grave, we will publish it here. In the meantime, feel free to take a look at the meal plans in the surrounding area. Or help us by making available the meal plan here.