Valkenburgsemeer Narrow Gauge – Industrial NG Museum near Leiden Posted on 30 August 2012 by pvelthoen Valkenburgsemeer museum depot 29-9-2008 Engine driver Gerard being dwarft by O&K B engine and in style wearing wooden shoes or “klompen” 29 September 2008 The O&K and workshop with driver Gerard de Graaf Restored part of the collection. The “has to be done” part is much larger … A 750 mm ex GTW staem tram trailer on the right.