Accurate, up-to-date, and high-resolution land use/land cover (LULC) maps are essential for environmental monitoring, spatial planning, climate resilience, and sustainable land management. Despite the increasing availability of Sentinel-2 imagery, existing publicly available datasets often lack explicit seasonal representation, consistent multi-year annotations, or thematic detail suitable for heterogeneous Mediterranean landscapes. To address these limitations, this study introduces S2GAIA, a multi-year, seasonally aware Sentinel-2 dataset for pixel-wise LULC mapping in Greece. The dataset is generated by harmonizing multiple geospatial sources, including Copernicus products and national datasets, into a unified 22-class taxonomy. S2GAIA comprises 34,030 annotated Sentinel-2 image patches (256 × 256 pixels) at 10 m spatial resolution, spanning the period 2017–2024. Each year is represented by four cloud-free seasonal composites, enabling the exploitation of phenological variability and improving the discrimination of temporally dynamic land-cover classes. The dataset was evaluated using four semantic segmentation architectures, with ResUNet achieving the highest performance, obtaining a Cohen’s Kappa coefficient of 91.23% and a weighted F1-score of 92.23%. Additional class-wise, confusion, and seasonal analyses demonstrate the effectiveness of the proposed multi-season design while identifying the remaining challenges associated with fragmented and spectrally similar land-cover classes. The resulting national-scale LULC maps demonstrate the practical applicability of S2GAIA for environmental monitoring and provide a valuable resource for developing and evaluating deep learning models for Mediterranean land-cover mapping. The S2GAIA dataset and the associated source code are publicly available through Zenodo (https://zenodo.org/records/21883467) and GitHub (https://github.com/eugeniapapathe/S2GAIA), respectively.

Climate-related and environmental hazards affect cultural heritage sites in markedly different inland, coastal, lacustrine and underwater settings, creating documentation requirements that cannot be addressed by a single sensing approach. This study presents the multi-sensor geometric documentation of eight cultural heritage sites. Unmanned aerial vehicle (UAV) photogrammetry was applied to six inland and coastal sites, while underwater photogrammetry, unmanned surface vehicles (USVs), acoustic sounding and a prototype green-wavelength flash LiDAR were used at three shallow-water sites. The campaigns produced orthomosaics, elevation models, dense point clouds, textured meshes, bathymetric maps and underwater LiDAR point clouds at scales appropriate to the conservation problem of each site. The resulting products document exposed architectural remains, excavation areas, cliffs and unstable slopes, lake-margin changes, submerged masonry, wooden structures and lakebed morphology. Their main contribution is the establishment of spatially explicit, site-specific baselines that provide measurable geometric and visual evidence for condition assessment, future repeat-survey comparisons and the spatial integration of environmental, archaeological and conservation information. The study demonstrates the operational and information complementarity of optical, acoustic and active ranging approaches, which address different documentation scales, environmental constraints and heritage targets, and provide distinct spatial evidence that can serve as potential inputs to subsequent digital twin and decision support applications.

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.

Protection of coastal cultural heritage is among the most urgent global priorities, as these sites face increasing threats from climate change, sea level rise, and human activity. This study emphasises the value of innovative geospatial tools and data ecosystems for timely risk assessment. The role of land administration systems, geospatial documentation of coastal cultural heritage sites, and the adoption of innovative techniques that combine various methodologies is crucial for timely action. The coastal management infrastructure in Greece is presented, outlining the key public authorities and national legislation, as well as the land administration and geospatial ecosystems and the various available geospatial ecosystems. We profile the Hellenic Cadastre and the Hellenic Archaeological Cadastre along with open geospatial resources, and introduce TRIQUETRA Decision Support System (DSS), produced through the EU’s Horizon project, and a Digital Twin methodology for hazard identification, quantification, and mitigation. Particular emphasis is given to the role of Digital Twin technology, which acts as a continuously updated virtual replica of coastal cultural heritage sites, integrating heterogeneous geospatial datasets such as cadastral information, photogrammetric 3D models, climate projections, and hazard simulations, allowing for stakeholders to test future scenarios of sea level rise, flooding, and erosion, offering an advanced tool for resilience planning. The approach is validated at the coastal archaeological site of Aegina Kolona, where a UAV-based SfM-MVS survey produced using high-resolution photogrammetric outputs, including a dense point cloud exceeding 60 million points, a 5 cm resolution Digital Surface Model, high-resolution orthomosaics with a ground sampling distance of 1 cm and 2.5 cm, and a textured 3D model using more than 6000 nadir and oblique images. These products provided a geospatial infrastructure for flood risk assessment under extreme rainfall events, following a multi-scale hydrologic–hydraulic modelling framework. Island-scale simulations using a 5 m Digital Elevation Model (DEM) were coupled with site-scale modelling based on the high-resolution UAV-derived DEM, allowing for the nested evaluation of water flow, inundation extents, and velocity patterns. This approach revealed spatially variable flood impacts on individual structures, highlighted the sensitivity of the results to watershed delineation and model resolution, and identified critical intervention windows for temporary protection measures. We conclude that integrating land administration systems, open geospatial data, and Digital Twin technology provides a practical pathway to proactive and efficient management, increasing resilience for coastal heritage against climate change threats.

The use of UAV photogrammetry has significantly enhanced the geometric documentation of cultural heritage sites, by providing - in a cost-effective way - high-resolution image datasets for accurate mapping and 3D modelling, monitoring, risk assessment and digital preservation. This paper explores the methodologies and applications of UAV photogrammetry, emphasizing its growing role in protecting endangered archaeological and historical sites. The paper begins by outlining UAV photogrammetry methodologies, with a focus on data acquisition (including both imagery datasets and ground survey), image matching procedures, image orientation and sparse reconstruction through Structure from Motion (SfM) processes, multi-view stereo pipelines for 3D point cloud creation and 3D model generation, digital surface model production and orthophoto creation. Additionally, the paper discusses the integration of UAV phot ogrammetry with other technologies, like LiDAR sensors as well as remote sensing imagery, outlines existing applications of machine learning for the further processing of photogrammetric products and discusses the combined use of the photogrammetric resu lts with GIS (Geographic Information Systems) and BIM (Building Information Modelling). Finally, the paper presents several case studies across cultural heritage sites in Greece, where UAV-based 3D modelling has been applied, demonstrating the potential of UAV photogrammetry and multi- image reconstruction procedures in efficient and accurate cultural heritage documentation of sites of varying characteristics with complex geometry.

Cultural heritage (CH) sites face increasing risks from climate change (CC) and various hazards, posing threats such as rising sea levels, extreme weather events, and environmental degradation, endangering their preservation and long-term existence. A lot of research has been done on protecting CH sites, but we still lack systemic approaches towards identifying and mitigating risks to CH sites. The TRIQUETRA EU research project proposes a technological toolbox and a methodological framework for tackling climate change risks and natural hazards threatening CH, in the most efficient way possible. The main strategic objectives of TRIQUETRA include: the creation of a repository of knowledge on effects of CC and natural hazards on CH, including lessons learnt from existing mitigation measures; the implementation of a systemic approach towards identification of upcoming risks and hazards to CH; and the usage of novel technologies allowing efficient and accurate quantification of threats to CH. The TRIQUETRA project’s methodology is structured around three fundamental stages: (i) identifying risks, (ii) quantifying risks, and (iii) mitigating risks, forming what is known as the “trifecta” approach. This approach constructs a robust framework for evaluating and addressing the following categories of risks: (i) climate-related risks; (ii) extreme water, snow and ice hazard risks; (iii) geological and geophysical risks; and (iv) chemical and biological hazard risks. Furthermore, it assesses the damage and failure modes of CH structures as well as the compounded effects of various environmental stressors on CH sites. TRIQUETRA will be validated in eight different CH sites across Europe. The main project results can be summarized as follows: a novel risk quantification framework for CH sites; an expanded knowledge base platform; a decision-support platform (TRIQUETRA DSS) including risk severity quantification tools and mitigation measure selection and optimization tools; novel protective materials; a novel flash LiDAR; water quality analysers; and a CH site digitization framework.

Preserving cultural heritage sites demands risk management strategies that capture site-specific vulnerabilities at fine spatial resolutions. The present study introduces a novel framework for flood risk assessments that bridges large-scale hydrological modeling and sub-meter-level hydraulic simulations to provide enhanced insights into potential impacts. Our approach employs state-of-the-art Rain-on-Grid (RoG) hydraulic simulations, targeted field data collection, and high-resolution geometric documentation using UAV imagery and GNSS ground control points to account for detailed terrain characteristics.Within the scope of the Horizon Europe TRIQUETRA Project, we apply this framework to the Apollo temple in the archaeological site of Kolona on Aegina Island, Greece. A total of 945 vertical and 4900 oblique UAV images were processed following a multi-image photogrammetric workflow, to produce a digital surface model with a resolution of 1 cm. We then use this data to set up the RoG model and to analyze flood scenarios for various return periods to obtain sub-meter-level hydraulic parameters and evaluate how the site’s vulnerability to flood intrusion might change if its existing wall obstructions were to be extended.The proposed methodology offers a robust means to extract high-resolution boundary conditions for advanced computational fluid dynamics simulations. Using our multi-scale workflow, relevant stakeholders can enhance their data-driven decision-making for cultural heritage protection and preservation purposes.Acknowledgments: This work is based on procedures and tasks implemented within the project “Toolbox for assessing and mitigating Climate Change risks and natural hazards threatening cultural heritage—TRIQUETRA”, which is a Project funded by the EU HE research and innovation program under GA No. 101094818.

The treatment of osseous defects around teeth is a fundamental concern within the field of periodontology. Over the years, the method of grafting has been employed to treat bone defects, underscoring the necessity for custom-designed scaffolds that precisely match the anatomical intricacies of the bone cavity to be filled, preventing the formation of gaps that could allow the regeneration of soft tissues. In order to create such a patient-specific scaffold (bone graft), it is imperative to have a highly detailed 3D representation of the bone defect, so that the resulting scaffold aligns with the ideal anatomical characteristics of the bone defect. In this context, this article implements a workflow for designing 3D models out of patient-specific tissue defects, fabricated as scaffolds with 3D-printing technology and bioabsorbable materials, for the personalized treatment of periodontitis. The workflow is based on 3D modeling of the hard tissues around the periodontal defect (alveolar bone and teeth), scanned from patients with periodontitis. Specifically, cone beam computed tomography (CBCT) data were acquired from patients and were used for the reconstruction of the 3D model of the periodontal defect. The final step encompasses the 3D printing of these scaffolds, employing Fused Deposition Modeling (FDM) technology and 3D-bioprinting, with the aim of verifying the design accuracy of the developed methodοlogy. Unlike most existing 3D-printed scaffolds reported in the literature, which are either pre-designed or have a standard structure, this method leads to the creation of highly detailed patient-specific grafts. Greater accuracy and resolution in the macroarchitecture of the scaffolds were achieved during FDM printing compared to bioprinting, with the standard FDM printing profile identified as more suitable in terms of both time and precision. It is easy to follow and has been successfully employed to create 3D models of periodontal defects and 3D-printed scaffolds for three cases of patients, proving its applicability and efficiency in designing and fabricating personalized 3D-printed bone grafts using CBCT data.

Cargo drones are a cutting-edge solution that is becoming increasingly popular as flight times extend and regulatory frameworks evolve to accommodate new delivery methods. The aim of this paper was to comprehensively understand cargo drone dynamics and guide their effective deployment in Greece. A 5 kg payload quadrotor with versatile loading mechanisms, including a cable-suspended system and an ultra-light box, was manufactured and tested in five Greek cities. A comprehensive performance evaluation and analysis of flight range, energy consumption, altitude-related data accuracy, cost-effectiveness, and environmental were conducted. Based on hands-on experimentation and real-world data collection, the study proposes a novel data-driven methodology for strategically locating charging stations and addressing uncertainties like weather conditions and battery discharge during flights. Results indicate significant operational cost savings (89.44%) and a maximum emissions reduction (77.42%) compared to conventional transportation. The proposed strategic placement of charging stations led to substantial reductions in travel distance (41.03%) and energy consumption (56.73%) across five case studies in Greek cities.

Cultural heritage (CH) sites are frequently exposed to natural elements, and their exposure becomes particularly precarious with the onset of climate change. This increased vulnerability places these sites at risk of deterioration or complete destruction. Risks such as land deformation, floods, acid rain, and erosion significantly threaten historic monuments, while water-related hazards, significantly influenced by both climate change and human activities, present a particularly grave risk to these invaluable sites. Considerable research efforts have focused on safeguarding CH sites. However, there remains a deficiency in systemic approaches towards identifying and mitigating risks for CH sites. The TRIQUETRA project proposes a technological toolbox and a methodological framework for tackling climate change risks and natural hazards threatening CH in the most efficient way possible. It aims at creating an evidence-based assessment platform allowing precise risk stratification as well as a database of available mitigation measures and strategies, acting as a Decision Support System (DSS) towards efficient risk mitigation and site remediation. TRIQUETRA is a European project that brings together a diverse group of researchers with varied expertise, encompassing university research groups, research institutes, public entities, as well as small and medium-sized enterprises. In this article, TRIQUETRAs overall methodology is presented, and preliminary results concerning risk identification, TRIQUETRAs knowledge base, as well as novel sensors and coatings, are discussed.

Digital Twin (DT) technology is the tool for monitoring, management and intervening in a timely manner to prevent disasters in urban areas, transforming them into smart cities. By enabling real-time data flow through utilizing a vast network of interconnected sensors and smart devices the functioning of buildings, facilities and utility networks can be monitored, managed and optimized to achieve a more stabilized, fair and sustainable urban environment. Good land management and optimal exploitation can also be achieved. The paper presents an innovative crowdsourced methodology for a fast, low cost and reliable structuring of the necessary geospatial infrastructure for a digital twin of an urban neighborhood by merging and visualizing individual BIMs with available open data, such as open orthophotos and cadastral maps, planning and building regulations, as well as existing land uses, smart devices and metric data derived from the Google Earth Pro and Street View platforms. The above-mentioned data if transferred into an open-source platform, such as Tandem, are ideal for tracking, managing and improving the residents’ living, from an economic, hygienic, safety and ecological point of view. Data derived from smart devices is a prerequisite for predicting and preventing various problems and setbacks.

Currently, there is a growing consensus that the use of more sustainable urban freight transportation has the potential to offer major energy and efficiency benefits which can be achieved through the appropriate combination of cargo bikes and the integration of drones into the urban logistics system. This study presents the results of a stepwise regression analysis that examines the role, benefits, and impact of electric vehicles such as e-bikes, cargo bikes, and drones for intermodal freight transportation in five Greek cities to support the green logistics paradigm. The results show that between routes of almost equal length, the most bicycle-friendly routes, such as routes along pedestrian areas or residential streets, should be avoided, as they reduce delivery speed and increase delivery costs in terms of energy and time expenditure. In addition, priority roads, which usually have higher traffic speeds and more trucks, are preferred by cyclists due to the quality of the road surface, even though the feeling of safety is lower on such roads. Finally, regarding drones, energy consumption is relatively low in the 0–5 mph and 6–10 mph wind speed ranges, indicating efficient energy use. In the 11–15 mph and 16–20 mph wind speed ranges, energy efficiency is significantly lower than the battery capacity, indicating that the cargo drone exhibits excessive energy consumption under these conditions.

This paper presents a holistic guiding methodology for the development of a geospatial tool to be used for the documentation, planning, smart management and dissemination of a country's network of historic hiking trails. To deal with the challenges and to ensure the sustainability of a historic site, geospatial documentation merging authoritative and crowdsourced data and a WebGIS-based spatial analysis is necessary. Geospatial data collection should include professional field surveys, professional and crowdsourced photographic documentation and video recording of the existing historic walking/hiking trails. A geodatabase, structured using relational model technology, including vector spatial entities (feature classes), mosaics (raster) and tabulated data (geodatabase tables), should be developed on a commercial or open platform; in this case, the ArcGIS Pro is used. Entities with embedded descriptive information and metadata for the technical, legal, historical, and administrative context may then be created. An object-oriented data model is needed to connect spatial and descriptive information. Spatial and descriptive queries or correlations between attribute fields of spatial entities must be enabled for specialized information retrieval by either experts or users. Next, a web GIS application to present the developed geodatabase in a visually appealing and informative way is created. It should integrate 2D maps with built-in tools and should support advanced functionalities, such as: (i) pop-ups that display brief information and images about specific spots along the trails; (ii) dynamic visualization of the vertical profile of each trail; (iii) multimedia information about landmarks, natural features and scenic viewpoints. Finally, the tool includes a feedback service and continuous efficiency monitoring and assessment, and enables adjustments, if and where needed. The tool is tested and used for 10 historical walking/hiking trails of the archaeological and Holy Site of Meteora, Central Greece. This is a UNESCO World Heritage site. The network, with a total length of 35 km, leads to six monasteries, still active since the 12th century, passing by gigantic rocks and beautiful natural landscapes. The site is famous globally and the greater area is continuously overcrowded with visitors. The tool is anticipated to be used for the documentation and management of the whole walking/hiking historic trail network of Greece in the future.

A technical tool to support projects for urban reforms and the implementation of current land policies is presented together with an example for its application in a project concerning the preservation of privately-owned residential buildings listed as “protected” cultural heritage (CH) constructions, urban planning and planning for affordable housing provision. The projects should be based on the voluntary participation of current property owners and an agreement signed between them and the private developer (team of professionals), so that the project will be self-financed through value capture measures to be decided by the state. The application presented here is based on the assumption that the state, by example, has set the rules for an increase in FAR in order to apply affordable housing policy and the preservation of listed CH residential private constructions. The state also provides the rules for identifying the target group of beneficiaries for affordable housing. Current property owners contribute the land, while the developer’s team undertakes all project costs. New property units are shared accordingly with the developer, the current owners and the beneficiaries for affordable housing. No additional public funds for the “affordable housing” units or for expropriation of the protected CH buildings is required.

The ongoing rapid urbanization has led to the emerge of several complex infrastructures distinguished by multi-dimensional and overlapping property rights. The option of integrating BIM data into LA, aligned with international standards and able to handle the three-dimensional (3D) aspect of cadastral objects utilizing contemporary technologies, may be of a great importance. The main objective of this paper is to investigate the potential integration of the Building Information Model (BIM) and the Industry Foundation Classes (IFC) standard, with the international standard of Land Administration Domain Model (LADM ISO 19152 2012), in order to provide a unified solution for the registration and visualization of 3D spatial and sematic information regarding the complex Rights, Restrictions and Responsibilities (RRR) in the new complex constructions. The proposed solution aims to exploit the available 2D plans for the generation of BIMs; and rely on international LADM’s constructional guidelines to provide a standardized cadastral database harmonized with the national Greek cadastral and the legal framework and aligned with the current Greek building code. The proposed framework is tested for two multi-storey buildings. The first results are promising constituting an important tool, for the implementation of 3D cadastres.

In most countries, three-dimensional (3D) property units are registered utilizing two-dimensional (2D) documentation and textual description. This approach has several limitations as it is unable to represent the actual extent of complicated 3D property units in space. As traditional procedures often lead to increased costs and long delays in 2D cadastral surveying, a fast, cost-effective, and reliable solution is needed to cope with the remaining global cadastral surveying needs. Crowdsourcing has claimed a critical role as a reliable methodology with huge potential regarding the realization of 2D and 3D cadastral registration in both an affordable and a timely manner. Many large modern constructions are now planned and constructed based on BIM technology all over the world. The utilization of 3D digital models, such as building information models (BIMs), and the establishment of a connection with the international standard of the Land Administration Domain Model (LADM) could be a solution for the rapid integration of these units into a 3D crowdsourced cadaster with a better representation of the cadastral boundaries of these units, a detailed visualization of complex infrastructures, and an enhancement in the interoperability between different parties and organizations. In this paper, the potential linkage between the BIM, the LADM, and crowdsourcing techniques is investigated in order to provide an effective technical solution for the integration of large new constructions into 3D crowdsourced cadastral surveys. The proposed framework is tested on a building block in Athens, Greece. The potential, perspectives, and reliability of such an implementation are assessed and discussed.

Augmented Reality (AR) is more than an added value for Cultural Heritage (CH); it is vital for its sustainability, promotion and dissemination, increasing accessibility in CH even during difficult periods of time, like the Covid-19 pandemic. In order to be meaningful and engaging, an AR application should have the following characteristics: easiness of use, high-quality representations and compatibility. This paper presents a marker-less mobile AR application for the display and inspection of high-resolution 3D cultural assets, overlayed on a particular location in the real-world scene. Instead of predefined markers, an image captured by the user is exploited as a pattern for real-time feature matching, pose estimation and scene augmentation. Our approach is based on pure computer vision and photogrammetric techniques, implemented using native C++ and Java code for Android mobile platforms. It is built with the use of the OpenCV library and the OpenGL ES graphics API without any dependencies of AR Software Development Kits (SDKs). Therefore, it supports cross-vendor portability regarding mobile model devices and hardware specifications. The evaluation of the developed application examines the performance of various matching techniques and the overall responsiveness of processing and 3D rendering on mid-range and low-end smartphones. The results showcase the reliability and responsiveness of the pattern recognition as well as the potential of the 3D graphics engine to render and overlay complex 3D models balancing between visual quality and time. The proposed methodology is applied to the Ciborium of the church of St. Charalabos, located at St. Stephen’s Monastery in Meteora, Greece.

The mission of digital Cultural Heritage (CH) repositories goes beyond engagement and dissemination; their research data should be approached and correlated spatially and semantically in the service of conservation and accessibility. Therefore, a flexible system is needed to expand, reuse and repurpose their content, addressing online collaboration, real time progress and ease of use. Towards this direction, the “METEORA” web-based platform is a novel and holistic approach to the organization, management and visualization of the 3D and 2D documentation products of CH sites. It integrates a multi-scale 3D viewer based on the 3DHOP framework, personalized information access and interactive tools for data retrieval and presentation. Emphasis is given in the development of a mid-level interface for creating, updating and maintaining 3DHOP’s functionalities and customizing information based on the user’s scientific specialty and field of interest. The proposed admin control panel updates the state of the current visualization, allows the integration of 3D models and multimedia and automates the creation of clickable points of interest on top of the 3D surfaces. It is based on a MySQL Relational Database Management System (RDBMS) that supports the back-end User Interface (UI) with create, read, update and delete (CRUD) management functions of a typical RESTful service. Moreover, all the control mechanisms as well as the procedures of authentication, authorization and encryption of the credentials of the certified users are configured through the PHP scripting language and JSON files. The resulting platform achieves maximum adaptability in digital archiving of heterogeneous datasets and has increasing efficiency in representing all types of data supported by 3DHOP.

The purpose of this paper is the investigation of the performance of four well-established commercial and open-source software packages for automated image-based 3D reconstruction of complex cultural and natural heritage sites, i.e., Agisoft Metashape, RealityCapture, MicMac and Meshroom. The case study is part of the inaccessible giant rock of St. Modestos, in the archaeological site of Meteora. In terms of computational time, the commercial software packages were the most time-efficient solutions, with Metashape being the fastest one. They also have a friendlier user interface, which makes them adoptable even by non-photogrammetrists. Αll four solutions yielded approximately comparable results in terms of accuracy and may be used for generation of 3D dense point clouds of complex sites. With the exception of Meshroom, they may produce georeferenced results. Also, with the exception of MicMac, which did not yield satisfactory results in terms of textured mesh, they may be used for generating photorealistic 3D models. The comparative analysis of the results achieved by the tested software will serve as the basis for establishing photogrammetric pipelines that may be generally used for 3D reconstruction of complex geometries.

Narrow space surveying and mapping is of high importance for many applications, with the demand for digital 3D models in a low-cost and relatively fast way growing rapidly. This paper examines SLAM-based and image-based mapping systems for indoor mapping and focuses on the comparison of the 3D point clouds acquired from two commercial mapping systems, Leica BLK2GO and Matterport Pro2 3D (MC250). Issues that are addressed include the effect of the mapping trajectory on the produced mapping result, and the amount of mapping propagation error in narrow space surveying. The two systems are experimentally compared against both an ideal geometric target facility and in an example environment of a narrow corridor. Finally, results are given with derived metrics that can be possibly extended to several real applications.