You do not need to get an FFN card in advance because you can get it and pay for it when you check into the campsite. You do not need it to get into the Naturist Quarter, which you check into first.
Basically you park up just before the barrier to the NQ, walk to the NQ office which is to the right of the barrier and check into the NQ, showing your booking for the campsite just to show you are booked in and to get your pass, which is a swipe card you use to get in and out if driving.
Then you drive into the Naturist Quarters, park up outside the campsite and walk into the campsite reception, showing your booking at the barrier to the campsite. The campsite will charge you for the remaining part you have to pay for your stay, plus the cost of the cards (roughly EUR15). The office closes at 8pm (20:00).
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