The ZAD of Notre_dame des Landes is an definitiv autonoumous zone that is settled 20 kms from Nantes, in France. For more information, please check this website.
In can sometimes be a little difficult to access this place, but if the website doesn’t mention anything, it should be quite easy. For the people travelling by car, you might have to park outside the ZAD. You can have plenty information here
We advice that you read some of the text on their website to get used to the ZAD and the way it works. You can for instance check what material is needed, to give a hand