Masonry structures in the Medieval towers of San Gimignano, Italy

The town of San Gimignano has a unique character due to the presence of numerous towers that rise above the roofs. The surviving towers offer a panorama of great interest due to the construction methods of using very thick walls, generally made of stone, with only a few exceptions where brick was used. One of the surprising aspects of the towers is the existence, in many cases, of solid masonry at the base, with no space inside, where the ground floor is a sort of continuation of the foundation above the level of the street. This part of the external masonry is constructed from limestone ashlars in regular rows, worked with the same accuracy as the upper facing. In some towers, such as in the ‘Becci’ tower, the solid masonry was later breached on the ground floor, creating a narrow corridor. In some others, such as the Cugnanesi tower, a breach highlights the inner core of mortar of excellent quality with stones and river pebbles. No less characteristic is the relationship between the building structures and the interior rooms of the towers, where the wall thickness which sometimes exceeds two meters, is combined with internal spaces a little more than a meter wide.