The article presents the experience of the Institute of Archeology of the Russian Academy of Science’s Markul Expedition, which utilized digital technologies for the study, preservation, and popularization of cultural heritage. The objective of the Markul Expedition was to obtain a complete picture of the historical and cultural landscape of Northwestern Colchis in antiquity by applying two key digital technologies: geographic information systems (GIS) and photogrammetry. The results obtained from the latter were used both independently and were integrated into GIS as separate layers (orthophotomaps, digital terrain models) or as hyperlinks to objects (3D models, videos, plans, sections, etc.). The objects investigated by the expedition are very diverse both in size and in terms of shooting conditions. Accordingly, each category of archaeological site required an individual approach, and a separate methodology and equipment. The final visualization angles differ to a fair extent from the original samples even though photogrammetry provides more accurate results than manual measurements. There are several reasons for this, including the vegetation, which is a dominant factor in the Caucasus subtropical area and led to partial visual distortions of the photographed objects. For this reason, the final projections of architectural forms required corrections and some hand drawing. In this process, new aspects appeared in the final result, resulting from the archaeologist and artist’s differing views of the objects. Our experience of using modern remote sensing technologies is also presented in the article.

The present study examined the references in the works of ancient authors to the ancient city and the Roman fortress Pitiunt, the geological aspects of the formation of the coastline in the Pitsunda Cape area in the first centuries AD and the results of archaeological research of the monument performed from 1952 to 1974. The creation of the 3D reconstruction of the exterior of the Pitiunt fortress during its prosperity in the IV century AD, along with the churches which were the first monuments of religious architecture in northwestern Colchis (northwestern Colchis comprises parts of the territory of modern Russia, Georgia and Abkhazia) was carried out based on the excavation plans and the principles of fortification and temple architecture that were accepted in the late Roman times, paying special attention to the geological paleoreconstructions.

In Late Antiquity and the Early Middle Ages, both coastal and sub-mountainous parts of Colchis underwent rapid urbanization. In the 12th century, the processes of decline began: Large settlements were replaced by small farmsteads with light wooden buildings, and the economy transformed from commodity-based to subsistence-based. What caused this decline? Was it the social and political events linked to the decline of the Byzantine Empire and changes to world trade routes, or were there other reasons? This article provides the answer. The synergy of archaeological, folkloristic, historical cartographic, climatological, seismological, and hydrological data depicts a strong link between these processes and climate change, which occurred at the turn of the 12th–13th centuries. The beginning of cooling led to a crisis in agriculture. A decline in both farming and cattle breeding could not fail to affect demography. Seismic activity, noted in the same period, led to the destruction of many buildings, including temples, and fortresses, and changes in hydrological networks, which were directly linked to climate change and caused water logging, led to a loss of the functions of coastal areas and their disappearance.

The 3D reconstruction of the Great Pitiunt Fortress has been our long-term goal. The results of archaeological excavations have revealed traces of a mosaic floor in one of the temples. It was impossible to carry out a full reconstruction of the temple without first restoring the mosaic floor. The area of the preserved mosaic found during the excavations was only 33 square meters. This is 10.5% of the total interior area of the temple of 317 square meters. However, based on a number of reasons, i.e., the direction of the dividing borders between the elements of the mosaic, the requirement of symmetry of individual sections, the adjustment of motifs and the analysis of similar contemporaneous sites, it was possible to make a version of the general view of the reconstructed mosaic floor for further processing in the 3D reconstruction of the temples of the complex. This article provides the methods described, an analysis and justification of the reconstructed design of the mosaic in fragments and a holistic final model. The stylistic features of the mosaic have been identified, and the reasons for the dating of the mosaic have been given.

The Markul settlement is an architectural site of the local population of northwestern Colchis. It is located in the village of Markula, Ochamchira region, Republic of Abkhazia. Traditional and modern digital methods are combined here to study the settlement. Panorama images acquired by a drone are used to outline a final orthometric model of the landscape of the entire settlement. An ancient road was discovered after detailed analysis of the finished model. Field studies have confirmed the existence of the road. Photogrammetry is similarly used here to study the architectural remains of the Alakhash-abaa tower and the results suggest that it was erected in the Roman period. The excavation results also support this conclusion.

For northwestern Colchis, many questions about both the ancient Greek colonization and the later Roman presence remain controversial. To a large extent, this is due to the poor preservation of the archaeological sites of the coastal area, which is one of the most dynamically changing natural formations. Therefore, one of the main objectives of the study was to investigate the paleo-landscape and paleo-climate of the area. At present, there is a lack of research in this area. For this purpose, a special GIS of the north-western coast of Colchis was created, which allows the summary, combination and analysis of data and results from various studies (historical, archaeological, paleogeographical, etc.), cartographic material (including historical coastline maps) and UAV surveys. In order to analyze the coastline of the study area, a series of maps were digitized. This allowed the different timelines of the coastline in ancient and medieval times to be represented in a GIS and combined with a modern map of the depth of the sea near the coastline. It was found that in contrast to modern times, the Black Sea coastline in the study area was more indented in ancient and medieval times, necessitating more detailed study of individual areas selected based on GIS analysis of the spatial location of archaeological sites. They were described, and soil samples were taken for further analysis during the field season of 2022. The discovery of a previously unrecorded Holocene marine terrace system was one of the interesting results of the survey. The analysis of the location of archaeological sites in GIS has shown that Byzantine and Medieval sites were mainly recorded on the coast. Ancient sites are mostly found in areas with strong accumulation of rivers (Pitsunda, Sukhumi Cape), while they are often located relatively far from the coast. The GIS currently contains information on 1 780 archaeological sites and will be updated with paleogeographic data on selected Holocene terraces and soil samples.