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Keywords from Image Description:
Siege of Grol Fortifications of the English Frisian and Hollandish troops J.Blaeu . en Schematic drawing of the fortifications and quarters made by the English Frisians and Hollanders during the Siege of Grol Groenlo in led by Maurice of Orange nl Schematische weergave van de schansen en kwartieren voor de Engelse Friese en Hollanse