From 16 July 1940 until 25 November 1941, Martijn Koppel stayed at the Villa Catharinahoeve, a Jewish youth farm in Gouda opened for Palestine pioneers on over two hectares of land in 1937.
A memorial in Den Haag commemorates the Jewish victims of this town. More information on this memorial can be found (in Dutch) on the website of the Nationaal Comité 4 en 5 mei.
Biography