In the treasury of the National Archives are two virtually unknown maps of the city of Nijmegen from the year 1750. They also include a unique sketchbook with an enormous series of measurements and detailed drawings. The maker of the sketchbook of these maps is the Groningen military engineer Klaas Willem Kiers. He was commissioned by Stadholder William IV to map the city and fortress, with the ultimate goal of creating a model of the strategically important Nijmegen. That model has been lost, but the preparatory drawings have been preserved. This is quite exceptional: many fortified towns do have a map, but the sketches that made such a map possible are missing. With the plans and detailed drawings, Kiers guides the viewer and reader back in time, along the streets, gates and fortifications of Nijmegen almost three centuries ago. Kiers' detail compels admiration. This book shows at what crossroads engineer Kiers, client Willem IV and the noisy city and fortress of Nijmegen met in the mid-eighteenth century. From the profusion of detailed drawings, a selection has been made that provides insight into Kiers' work and the wealth of surviving material.