Italian journal of engineering geology and environment

Presentation

Gabriele Scarascia Mugnozza — 2025-09-30

The TRIQUETRA project

Charalabos Ioannidis — 2025-09-30

The geometric documentation of the Greek cultural heritage sites participating in the TRIQUETRA project

Charalabos Ioannidis — 2025-09-30

In the light of threats including climate change, geological degradation and extreme weather conditions, the geometric documentation of cultural heritage sites plays a crucial role in their preservation. Photogrammetric techniques enable the production of highly accurate 3D models, orthoimages, and digital surface models (DSMs), which facilitate both site monitoring and conservation planning. This article presents the photogrammetric documentation of three archaeological sites in Greece, namely, the archaeological site of Aegina Kolonna, the Sunken City and the coastal cultural heritage of Ancient Epidaurus, as well as the sanctuary of Kalapodi. The geometric documentation of all three sites was conducted within the framework of the TRIQUETRA EU-funded project, through ground surveys and UAV-based photogrammetric techniques, either independently or in combination with underwater photogrammetry workflows, in order to capture the geometry of the cultural heritage sites and their surrounding environments. The produced results include 3D dense point clouds, 3D textured mesh models, DSMs and high-resolution orthomosaics. The generated datasets support detailed structural assessments, vulnerability analyses and risk assessment studies, providing a fundamental basis for protection efforts of the archaeological sites of interest.

Preserving underwater cultural heritage: combining satellite images with a novel flash lidar platform

Eleonoor Bosch — 2025-09-30

Les Argilliez, part of the UNESCO World Heritage Site “Prehistoric Pile Dwellings around the Alps,” is in Lake Neuchâtel (Switzerland) and dates to the Classical Cortaillod (3841-3817 BC) and Late Cortaillod (around 3500 BC) cultures. Among other artifacts, it consists of 4,834 wooden piles found over a 7000 m2 area ranging from 2 m to 3 m depth below the water surface. Two dangers threaten the preservation of the site: erosion and the proliferation of invasive mussel species: Dreissena rostriformis bugensis (quagga mussel) and Dreissena polymorpha (zebra mussel), which pose the specific threat risk of degrading the wooden piles. This study presents two methods developed for the monitoring of the erosion and mussel populations at Les Argilliez: a new flash lidar based 3D imaging platform and satellite image data analysis. Together, the two data collection schemes allow for efficient identification, quantification and tracking of environmental risks threatening underwater archeological sites, such as this one. The flash lidar is optimized for underwater applications and designed to collect 3D point cloud data from a medium-sized unmanned surface vehicle (USV). The lidar system is batterypowered and features a 128×128 pixel focal plane array for high resolution point cloud capture. When mounted to the USV, the lidar enables regular and efficient lake surveys, allowing consistent comparison of the same locations over time. The point cloud data enables measuring the height and orientation of the wooden piles and the lakebed profile. The first demonstrative lidar measurement results are presented in this study. In addition, spectral data from satellite images taken by Sentinel-2 was compared with simulated reflectance spectra for sand, macrophytes and mussels. The processed satellite data successfully identifies spectral anomalies correlated to the proliferation of quagga mussels in the area over a period of four years, and is confirmed by underwater surveys done by divers.

Exploring the Unesco world heritage property in the shallow waters at Rose Island using unmanned surface vehicles (USV)

Stefan Plattner — 2025-09-30

Rose Island (Germany) is part of the UNESCO World Heritage site “Prehistoric Pile Dwellings around the Alps” and a pilot site of the EU funded project TRIQUETRA, which targets the risks of climate change on cultural heritage. With the lack of a detailed bathymetric map of the waters around Rose Island and in search for an efficient approach for documenting the wooden relics from Iron Age at the lake bottom, both a sonar and a photogrammetric campaign were conducted by the German Aerospace Center (DLR). From the sonar measurements, the first reliable bathymetric map of the area was generated and provided to TRIQUETRA’s decision support system and WebGIS. During the photogrammetric survey, ~15.000 high resolution images of the lake floor were taken by an unmanned surface vehicle (USV) and processed to high-resolution 3D models by using the structure-from-motion method (SfM). The models provide an unprecedented level of detail for the documentation and examination of the archaeologic remains at Rose Island and a fascinating insight to the prehistoric settlement remains for the general public.

Climate change and archaeological heritage: risk identification and monitoring of a lakeshore archaeological site in Smuszewo (Poland) - A case study

Renata Graf — 2025-09-30

The aim of this paper is to present a multi-level approach to risk identification and monitoring strategies for the lakeshore archaeological sites. Within a range of the cultural heritage typologies that are addressed by the TRIQUETRA project, the Late Bronze Age/Early Iron Age fortified settlement at Smuszewo (Poland) occupies a transitional position between mainland and water environment. Archaeological excavations and other surveys conducted between the 1950s and 2010s revealed wellpreserved wooden structures on land and on the east shore of Czeszewo Lake. Crucial to their preservation is the waterlogged environment which is directly related to the condition of the lake, water balance and particularly the water level. The problem of deteriorating water conditions (e.g. decreasing water level) in neighboring areas - resulting in recurrent droughts – has already been identified. However, its impact on the fragile wooden relics of the fortified settlement has not yet been assessed.

Remote sensing-supported monitoring of natural and anthropogenic hazards to cultural heritage in Ventotene and S. Stefano islands, Italy

Daniele Cerra — 2025-09-30

Cultural heritage sites are increasingly at risk due to climate change and environmental hazards, which can include floods, erosion, and ground instabilities. Climate forcing may also favour the impact of more severe anthropogenic hazards, as in the case of wildfires. In this framework, remote sensing may provide hazard quantifications and risk assessment, supporting the definition of conservation planning and protective measures. This study explores the analysis of optical satellite images to monitor and assess natural and anthropogenic threats to Ventotene and Santo Stefano islands, Italy. Specifically, we quantify damage by wildfires nearby cultural heritage sites from 2017 to 2024, while multispectral images allow a first assessment of bathymetry around the islands and deriving water constituents parameters. This enables a more comprehensive hazard analysis with a lookout on the process understanding and
definition of the risks these sites face.

The imperial villa of Punta Eolo (Ventotene) between archaeological evidence and geological assets in a conservation perspective

Alessandra Pegurri — 2025-09-30

The island of Ventotene, part of the Pontine Archipelago, is home to the remains of an imperial Roman villa at Punta Eolo promontory, a site threatened by severe hydro-geological risks. Since 2023, this site has been a key focus of the EU-H2020 TRIQUETRA Project, which aims to analyze and mitigate environmental threats to cultural heritage. The research integrates geological and archaeological investigations, combining highresolution photogrammetry, geophysical surveys, and material analysis to assess the site’s conditions. Geological studies reveal a complex stratigraphy of lava and tuff formations, influencing coastal erosion and landslides, which endanger both the site and its historical structures. Archaeological surveys reassess the villa’s architectural evolution, identifying multiple construction phases and previously undocumented features. The project also evaluates material degradation, particularly in wall plasters, frescoes, and pavements, correlating deterioration patterns with environmental stressors. Through GIS-based mapping and laboratory testing of building materials, the study aims to develop tailored conservation strategies, ensuring the long-term safeguarding of this invaluable site. The TRIQUETRA Project represents a multidisciplinary effort to establish conservation models applicable to other heritage sites facing similar geological and climatic challenges.

Kalapodi, Greece: the problem of frost at the archaeological site and the implementation of the TRIQUETRA programme

Artemios Oikonomou — 2025-09-30

In central Greece, in today’s Fthiotis, where in antiquity Phokis bordered eastern Lokris and Boeotia, there is a sanctuary that is one of the most important of ancient Phokis. Systematic excavations were carried out in the sanctuary in the second half of the 20th century, under the direction of the German Archaeological Institute and they continue to this day. As part of the TRIQUETRA programme an integrated methodological model to protect archaeological remains at Kalapodi from frost is proposed. The TRIQUETRA project (EU HE research and innovation programme under GA No. 101094818) aims at creating an evidence-based assessment platform that allows precise risk stratification, and also creates a database of available mitigation measures and strategies, acting as a Decision Support Tool towards efficient risk mitigation and site remediation (Ioannidis et alii, 2024). This paper will present climatic data of Kalapodi together with materials analysis of the building materials of the sanctuary highlighting the frost problem.

Engineering-geological and geophysical surveys for archaeological risk assessment in view of mitigation measures at Aegina Kolonna, Greece

Alexander Sokolicek — 2025-09-30

The archaeological site of Aegina Kolonna, a prominent cultural heritage landmark in Greece, is increasingly threatened by geological hazards, including coastal erosion, seismic activity, and slope instabilities. The progressive retreat of the calcarenite sea cliffs has already led to the loss of unexcavated historical remains, posing a severe risk to the site’s longterm preservation. Within the framework of the TRIQUETRA (Toolbox for assessing and mitigating Climate Change risks and natural hazards threatening cultural heritage) European Project, an interdisciplinary approach that integrates engineeringgeological, geophysical, and archaeological investigations has been adopted to assess site vulnerability and implement targeted mitigation strategies. A comprehensive geological survey identified the primary factors driving cliff instability, while ambient seismic noise measurements helped characterize the subsurface conditions and assess local seismic amplification effects. The structural stability of key archaeological elements, such as the last standing column of the Apollo Temple, was also evaluated, revealing resonance frequencies in the range 5-8 Hz, which may influence its seismic vulnerability. In addition to hazard assessment, the TRIQUETRA project focuses on heritage conservation of this site, particularly of the northeastern prehistoric settlement. Past restoration efforts relied on cement-based mortars, which have deteriorated over time, leading to structural instability. To address this, new interventions include detailed documentation, the replacement of degraded materials with lime-based mortars, partial backfilling to stabilize exposed foundations, and the implementation of long-term monitoring strategies. These measures aim to enhance structural resilience while adhering to international heritage conservation guidelines. This study underscores the necessity of a holistic approach to cultural heritage management, demonstrating how scientific research and restoration practices can be integrated to mitigate geological and environmental risks and ensure the sustainable preservation of archaeological sites.

Innovative methods for safeguarding cultural heritage

Kyriacos Themistocleous — 2025-09-30

Cultural heritage sites constitute irreplaceable records of human history, illustrating the progression of our social, architectural, and cultural practices. Increasing threats from climate-related hazards, such as shifting rainfall patterns, escalating temperatures, and intensified extreme weather, combined with geological and physical risks like landslides, earthquakes, and erosion, render these sites increasingly vulnerable. Earth observation technology is pivotal in preserving cultural heritage by improving documentation, enabling more effective monitoring, and supporting proactive conservation strategies. Recently, with advances in technology, advanced 3D scanning and imaging techniques, such as laser scanning and photogrammetry, have captured precise digital records of cultural heritage sites, documenting and helping conservators measure changes over time and swiftly identify structural vulnerabilities. Remote sensing technologies, including satellite imagery, aerial photography and UAV-based surveys, allow for extensive site evaluations, reducing risks and costs associated with onsite inspections, especially in remote or hazardous locations. Methodological frameworks and technological developments, encompassing remote sensing, satellite and aerial imaging, digital modeling with laser scanners, photogrammetry, and participatory data collection, are creating fresh opportunities for proactive, evidence-based conservation. Data-driven tools such as sensor arrays and digital twin models enable continuous monitoring, where real-time structural and environmental information is integrated into predictive models to anticipate emerging threats. This paper provides a comprehensive review of innovative remote sensing methods for safeguarding and monitoring cultural heritage under these compounded vulnerabilities. It focuses on integrating techniques employing remote sensing, geodetic methodologies, synthetic aperture radar, unmanned aerial vehicles (UAVs), digital twin platforms, and participatory data collection initiatives with sensors and crowdsourcing. A key emphasis of this study is the integration of state-of-the-art techniques for monitoring cultural heritage assets. Examples of various studies conducted in Cyprus, more specifically the case study of the Neolithic UNESCO World Heritage Site of Choirokoitia, demonstrate the practical application of these frameworks, highlighting the TRIQUETRA project (funded by the EU Horizon Europe research and innovation programme) with an innovative integration of conventional and novel methodologies for risk quantification, site monitoring, and stakeholder participation. The findings underscore the critical necessity of interdisciplinary collaboration, sustained funding mechanisms, and robust policy support to ensure the long-term preservation of cultural heritage for future generations.

An advanced knowledge base platform and a decision support system for safeguarding cultural heritage

Anastasia Anastasiou — 2025-11-05

The TRIQUETRA KBP, a core component of the TRIQUETRA DSS, comprises two key elements: a comprehensive database housing all outputs from the project’s literature review and a WebGIS platform integrating data from pilot CH sites such as Aegina, Choirokoitia, Epidaurus, Kalapodi, Les Argilliez, Roseninsel, Smuszewo, and Ventotene. As a dynamic electronic repository, the KBP offers extensive data and advanced search tools for efficient information retrieval. The TRIQUETRA project aims to develop a robust, evidence-based DSS to mitigate the impacts of climate change on CH monuments. The DSS toolbox includes the Risk Severity Quantification module and the Mitigation Measure Selection and Optimisation module. The latter provides tailored mitigation measures for each pilot site, offering tangible recommendations for risk mitigation through a multicriteria search feature that allows filtering based on cost, timeframe, and topological effects (Ioannidis et alii, 2024). Designed for adaptability and scalability, the module leverages the KBP database to propose solutions by assessing site compatibility with others facing similar hazards. Supporting advanced research, it facilitates informed decision-making, enhanced monitoring, and tailored preservation strategies, contributing to the long-term protection of CH sites.