caption: The image shows a drawing of a building with a gate and a wall, which is the entrance to the Königliches Oberbergamt in Bonn. The drawing is on a piece of paper with some text written on it. The gate is intricately designed with intricate details, and the wall is decorated with a pattern of small circles and lines. The text on the paper provides further information about the gate, such as its size, shape, and other features.