Starting monday October 11th 2021 the Postweg is closed. This means you have to take a different route to the park. Coming from the ferry you take the Pontweg.
Stay on the Pontweg until the rounabout, take the second exit
Take the first exit on the rounabout (Akenbuurtseweg)
Turn right on the second road you encounter (Georgiëweg)
Stay on the Waalderweg
At the rounabout, take the third exit (Zaandammerdijk)
Stay on the Zaandammerdijk until the Muyweg, go left.
Enter the first road on the left (Postweg)
Enter the first road on the left (EuroParcs)