Unfortunately, the zoo is no longer open to the public and is now an abandoned area.
There is still a monkey alive: https://www.ad.nl/home/aap-leeft-ruim-30-jaar-in-leeg-dierenpark-wassenaar~ab4123c1/?fbclid=IwAR0ey6WW7riO6st_SgPMwoLPGnwkNsmugW918edLQvGbDwop6-6_rofHzco