The Westerweel group provided protection to Jewish children and young adults at the assorted hakhsharah institutions. Joop Westerweel organized underground training for the children of the youth aliyah in the Loosdrechtse Rade. There he met Joachim Simons, who warned him about the horrors of the Nazi concentration camps. The resistance group associated with the Westerweels arranged places to hide for a great many young adults. Small groups fled to Spain and Switzerland via Belgium and France. At least 60 young adults reached Spain.
See also: Werkdorp Wieringermeer.