On the grounds is the house of the zookeeper, Willa Żabińskich, where real drama occurred during World War II. Back then, Jan Żabińskich and his wife Antonina lived here. The two hid dozens of Jews in animal cages from the Nazis, and saved their lives while risking their own. It's an incredible story that they were able to keep the Jews hidden from the Germans, when a German unit was placed right inside the zoo itself.
For saving 300 of Warsaw's Jewish residents, the couple received the "Righteous Among the Nations" award.