The court architect Ennemond Alexandre Petitot, by the will of the minister du Tillot, designed the monument of the Ara Amicitiae, which would rise in the center of the current square Piazza Garibaldi, as a symbol of the friendship between the dukes of Parma and the Austrian ruling house. Although almost nothing is left of that beautiful white marble artifact, it remains an interesting iconographic documentation in the form of drawings, engravings and models, which are to be considered of that period. This one, a wood model treated with plaster, it is to be considered the most ancient and valuable.