 The arch solved the problem of a site where two roads intersected at right angles, and allowed the foot traffic of the pilgrims to proceed above the road, Via Saragozza, uninterrupted.The architect was Carlo Francesco Dotti won the commission during a competition in 1714, and created the scenographic arrangement with the help of Francesco Galli Bibiena during 1721 to 1732.In the early twentieth century, in a project supervised by Tito Azzolino, the arch was raised a few meters to allow passage of a train underneath.