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Archaeologists can increasingly profit from digital elevation models for study and analysis of the actual landscape, which can contain signs of the past or mirror the ancient landscapes. From among the techniques available for such analyses, a photogrammetric method was chosen here that used images acquired by an unmanned aerial vehicle and involved structure-from-motion algorithms during the process. These methods were selected because as the state-of-the-art of the discipline they are in the initial stages and are under continuous evolution. Furthermore, they provided us with the possibility of rapid, highly automated, and also low-cost, production of high-resolution three-dimensional data. This test was carried out on the Roman site of Burnum(Croatia). It focused on the comparison between the digital surface model created using an unmanned aerial vehicle with a structure-from-motion approach, and the digital terrain model already built through a kinematic Global Navigation Satellite System survey. The results of the validation provided a final vertical accuracy of about 10cm, which was achieved in specific areas where there were no trees, bushes and high grass. Through the resulting digital terrain models, archaeologists can provide vital support for important hypothesis regarding the ancient environment.

Monitoring the time history of structures and infrastructures has always been an important area of application of geodetic and geomatic methods. Here we shall concentrate on the item of monitoring ancient buildings because, beyond its intrinsic interest, it provides a good illustration of some of the most recent monitoring techniques. Identifying the overhang, progressive changes of inclination, differential movements of the structure and detailing the study of structural elements are just some examples of the many fundamental and necessary information for structural engineers. Those data are required to study and analyze the behavior of a structure with the purpose to assess the stability. Looking at the several methods offered by Geomatics, laser scanning appears to be the best technology to provide an effective 3D solution to those requirements. Surveying by means of a terrestrial laser scanner, allows to detect a huge number of 3D information with high accuracy in a relatively short time and high accuracy. Just analyzing the point clouds, interesting information along with useful products can be obtained in order to draw some considerations about the investigated structure. This research aims at suggesting a new philosophy for using 3D models in a diagnostic perspective in order to study structures along with their actual dimensions, their stability and so on. Traditionally, indeed, laser scanning is chosen for artistic and architectural studies and the resulting three-dimensional model represents what often is of concern. Furthermore, the use of more classic techniques, such as total station and digital leveling, and LST is fundamental as an integrated approach for the monitoring of ancient buildings. The integration of different techniques allow a redundancy of observation and the possibility to verify the results obtained form independent techniques as is shown throughout some experimental applications.