You are standing precisely under the archway of the old Porta del Lago, the main gate of the second circle of walls: its name derives from the fact that the outer face of the gate overlooked the "Lake", actually a small pond designed to protect the walls at their most vulnerable point.

The walls used to run along the little garden you see on your left, and along the inside they were overhung by a canopy that protected street vendors from the weather. The care and maintenance of the Lake were entrusted to the parishes of S. Emiliano and of Matigge. It was drained and back-filled with earth in the late 18th century, and the gate and walls were pulled down in 1909.

Northeast of the Lake — where the hospital now stands — there stood until 1620 a little hill called "Montarone delle forche" (Gallows Mound) because capital executions were held there. The mound was leveled in order to build S. Domenico, a convent for Dominican brothers.