The Hornsby Shire Historical Society is housed in the Joseph Collingridge Hall, in Kenley Park, Normanhurst. The chairperson is the indefatigable Mari Metzke.
https://hornsbyshirehistoricalsociety.org/
https://historymatters.sydney.edu.au/2020/11/hornsby-historical-society-rediscovering-local-history/