On 19 June 2023, the WiB members had a guided tour through the Humboldt Castle, the hidden gem on the Tegeler See, which is still privately owned and inhabited by the descendants of the Humboldt family. Wilhelm von Humboldt, the philosopher, linguist and founder of the Berlin University, and his brother, the naturalist Alexander von Humboldt, spent their childhood here. After Wilhelm von Humboldt retired from public service In 1819, he returned to his parents' house and hired Karl Friedrich Schinkel to design both the interior and exterior of the renaissance building in classicist style. The largely preserved rooms reflect the spirit and the mindset of the Humboldt family. They are the impressive example of the dynamic appropriation of antiquity in that era. The one hour and a half tour flew while the WiB members were still immersed in the living history.