The image displays the Kastellet Windmill, located within the Kastellet fortress in Copenhagen, Denmark

The image displays the Kastellet Windmill, located within the Kastellet fortress in Copenhagen, Denmark. The structure consists of a red-painted octagonal base featuring white-framed rectangular windows. Above this base, a wooden observation gallery, supported by dark beams, encircles the windmill. The main body of the windmill is a dark, shingled conical tower, which includes multiple white-framed dormer windows. Four large, lattice-structured wooden sails extend from the top of the tower, positioned against a clear, bright blue sky. The windmill stands on a green grass lawn, which exhibits areas of strong sunlight and distinct shadows. In the background, numerous bare deciduous trees are visible, and a red-roofed building is partially discernible in the distant right. No people or interactions are visible.