# Advanced Technologies for Geosite Visualization and Valorization: A Review
## 3 Examples of Geoheritage Visualization and Valorization through Innovative Technologies
[107] created a trip to the Greek island of Salamis by using an interactive, GIS-tailored, story map application. [PERSON] et al. [108] created nine VGs in Santorini Island (Greece) through photogrammetry based on UAV-collected images, followed by 3D modeling. Subsequently, VGs have been put into a WebGIS environment, available online and thus suitable for geoscience communication and teaching. The Virtual Geostes can be accessed by way of a smartphone, a PC, or a tablet. Each VG is described in detail and contains a lot of annotations, which the users can access during 3D navigation (Figure 2). VR is a cutting-edge method that enables conducting 3D analyses in Earth Sciences, geoinformation for data gathering and dissemination, and, of course, an immersive experience for the users. Today, VR scenarios can be based on appositely produced geospatial datasets that include digitalized terrains and photogrammetry-created 3D models. The latter, as seen above, can be offered as virtual outcrops and geosites, and can be considered a crucial tool for solving typical difficulties experienced by students, enabling the viewing of 3D concepts on a 2D arrangement, or a virtual tour composed of images [109; 110; 111]. In 2010, a novel approach was proposed, represented by a series of 3D models that can be viewed in a similar way to a virtual tour, through a PC, a tablet or a smartphone; for instance, [PERSON] et al. [112] used this method, applying it to petroleum geoscience. Figure 1: Example of a Virtual Geosite showing a series of subvolcanic units in East Iceland. Observe annotations that help the virtual observer to gain insight into the features of the Virtual Geosite. 1: Vertical basaltic dyke. 2. Basaltic lavas. 3. Vertical basaltic dyke. 4. Inclinded sheet. 5. Vertical basaltic dyke. 6. Vertical basaltic dyke. 7. Vertical basaltic dyke. Modified after [PERSON] and [PERSON] [83]. [PERSON] et al. [113] have pointed out that VR applications can be regarded either as non-immersive, or fully immersive experiences. Non-immersive VR entails 3D visualization, in which the models are displayed on a PC screen and/or smartphone, without using any head-mounted devices. On the contrary, immersive VR is being increasingly used on occasions such as dissemination events and offers to the viewers a number of virtual ways to navigate through geosites, flying over appositely created scenarios, with the aid of VR thumbsticks and headsets. The viewers, in this way, can have an overall experience of a virtual geosite, which enables them to identify and observe various elements of a geological landscape or a geosite at different scales [114, 115]. During the last ten years or so, many cheap options have been offered so as to allow for an easy, immersive VR experience. Such new options are represented by both hardware and software solutions, and this has offered professors, students, and scientists a number of cutting-edge tools that can be applied to geosciences [116, 117]. As illustrated by [PERSON] et al. [118], at nine VR-based activities which took place in 2018 and 2019 at several sites (in Austria, Italy, and Greece), a great amount of participants had a chance to experience immersive VR across scenarios built through innovative, UAV-based photogrammetry methods. The VGs picked for organizing the events are stunning volcano-tectonic environments, with great historical, cultural, educational and scientific value. These are as follows: an awesome on-land triple-junction [119] and the 1984 Krafla eruptive zone [104], both situated in the Icelandic North Volcanic Zone (NVZ); Mt Pizzillo, located in the NE rift of Mt Etna [120] and the Metaxa Mine (Figure 3), a major touristic site on the island of Santorini [92]. The immersive VR application by [PERSON] et al. [118] featured scenarios that were built through UAV-based photogrammetry techniques, which result in virtual landscapes (3D models), which have centimetric, pixel size resolution.