The case study of Albani and Clementina towers

(Dipartimento di Architettura, DIDA UNIFI, Florence University, Italy)

Keywords: Coastline towers, Adriatic Sea, military architecture, Papacy, photogrammetry survey

Along the Mediterranean coast, the fortification system of towers has always the function to prevent and defend the coast from all the attacks, often of pirates. This kind of system is a planned and wellorganized network also in the Adriatic sea, where during the XIII century the Papacy and the Republic of Venice militarily controlled the sea. The choice of the case study, the Torre di Albani in Montignano, near Senigallia (AN), built in the XIII century, has served for the analysis of the historical and technological aspects that characterized the towers in this part of Adriatic sea in the Modern Age.
Interesting is also the comparison with the Torre Clementina in Portonovo (AN) built in 1716 by Pope Clement XI, 30 km far from Montignano, tower of a different period, but with the same relationship between the tower and the territory. It appeared immediately evident the need to have exact metric references since it is a strong offset towards the sea side. In order to process a photogrammetric survey, photographs were taken around the tower, which allowed to select 183 photos that were used during 3D alignment using the Agisoft Photoscan. The dense point cloud resulting from alignment has a high quality, with over 23millions points. After appropriate point cleaning with the 3D System Geomagic software, the resulting mesh model of 20 million polygons maintains the right relationship between data quality and data management ease. At the end, a rebuilding of the UV map has allowed to get a high-resolution texture map (16384 px).
This work aims to document and show all aspects of the tower, the construction type, the materials and the building model and to be able to analyze the different characteristics of the towers in order to better interpret the defensive system of the Adriatic Sea.