The drawing is signed by Luigi Marchesi and dated 1850. It's a preparatory study representing a view of the Piazza Grande in Parma. The view, with a vertical setting, focuses on the south-west corner of the square and in particular on the facade of San Pietro. The church designed by Petitot is in fact the focus of the scene and is the backdrop to the square teeming with people during a market day; in the foreground you can see the tents, the various street vendors and many figures intent on buying or simply walking in the square, around the Ara Amicitiae, the monument designed by Petitot and erected in 1769 to celebrate the visit in Parma of the Emperor Joseph II of Habsburg. One of the gas lamps installed in the city shortly before the mid-19th century is visible in the near area.