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Keywords from Image Description:
Siege of Grol Groenlo schematic image of recess and trenches J.Blaeu . en Schematic image of 'reduit' recess and trenches during the Siege of Grol Groenlo of by Maurice of Orange nl Schematische afbeelding van een 'reduit' vluchtschans en 'trenchee' loopgraven tijdens het Beleg van Grol Groenlo van door Maurits van Oranje Atlas