In February 2005 and July 2006, teams from the Development of Integrated Automatic Procedures for the Restoration of Monuments (DIAPReM) from the University of Ferrara, the Institute of Science and Information Technology of the National Research Council in Pisa and the Department of Architectural Design at the University of Florence conducted a High Definition Survey of the Piazza del Duomo. The data was acquired from 30 positions and was focused on the exterior parts of the Cathedral, the Campanile and the Baptistery. The 3D survey was coordinated and georeferenced with a topographical survey conducted by the DIAPReM team. The final 3D laser scan survey data was registered within the topographic survey with an average error of 3mm and fused into a master dataset (point cloud) that contains a total of 256,653,388 points.