Making the invisible visible:Underwater Malta—a virtual museum for submerged cultural heritage

The seabed can be considered as the world’s largest museum, and underwater sites ex‐ plored and studied so far provide priceless information on human interaction with the sea. In recog‐ nition of the importance of this cultural resource, UNESCO, in its 2001 Convention on the Protection of the Underwater Cultural Heritage, determined that objects/sites should be preserved in situ, whilst also advocating for public access and sharing. The implementation of these principles is not without difficulties. Some states have opened up underwater sites to the public—mainly through diving, yet the vast majority of the world’s population does not dive. In Malta, 7000 years of human occupation is reflected in and on the landscape, and recent offshore surveys show that the islands’ long and complex history has also left an indelible mark on the seabed. Besides difficulties related to their protection and management, these sites also present a challenge with regard to sharing and communicating. Recent advances in underwater imaging and processing software have accelerated the development of 3D photogrammetry of submerged sites and the idea for a virtual museum was born. The virtual museum, UnderwaterMalta, was created out of a need to share the plethora of underwater sites located on the seabed of the Maltese Islands. A multitude of digital tools are used to share and communicate these sites, offering visitors a dry dive into submerged sites that would otherwise remain invisible to the vast majority of the public. This paper discusses the basic principle of the sharing of underwater cultural heritage and the difficulties that beset the implementation of such a principle. A detailed explanation and evaluation of the methods used to gather the raw data needed is set in the context of the particular and unique working conditions related to deep water sites. The workings of this paper are based on first‐hand experiences garnered through the record‐ ing of numerous wrecks over the years and the creation and launch of The Virtual Museum‐Under‐ water Malta—a comprehensive virtual museum specifically built for “displaying” underwater ar‐ chaeological sites that are otherwise invisible to the general public.peer-reviewe

From discovery to public consumption : the process of mapping and evaluating underwater cultural heritage in Malta

The in situ promotion and preservation of underwater cultural heritage sites is one of the main ideas of the UNESCO Convention on the Protection of Underwater Cultural Heritage. Currently, most shipwrecks are found in water shallower than the 50 m contour. The continued technological advances and increases in technical diving and deep‐water exploration point towards a shift in this statistic, which is set to increase exponentially in the not‐too‐distant future. Thus, it is imperative to look at ways in which such directives can be implemented. This paper will highlight the synergy between existing remote sensing technologies and the management of underwater cultural heritage with examples of on‐going research projects, such as Malta’s approach to surveying and implementing a scoring system for historic wreck sites based on local and global considerations of historic and natural conditions of site elements. Such an approach allows for the scaling of sites based on a number of parameters and provides instructive information for the creation of management strategies. The intention here is to demonstrate how large‐scale remote sensing surveys can make major contributions to site management, which, in turn, facilitates the decision‐making process in terms of how and what information is transmitted to divers and members of the public.peer-reviewe

The innovative and state of the art public access management of Malta’s underwater cultural heritage

The obligation to preserve underwater cultural heritage is a core principle of the UNESCO Convention on the Protection of the Underwater Cultural Heritage. A key element of this obligation is a balance of scientific research, protection, and the promotion of responsible access to underwater cultural heritage sites. Such a balance requires the setting up of a network of communication between the tourism and heritage sectors on the one hand and the maritime and diving communities on the other hand. A variety of approaches have been developed to promote responsible access to underwater cultural heritage sites, and since the vast majority of the public does not dive, this also includes the development of virtual access. In Malta, maritime archaeology can be traced to humble and sporadic beginnings in the 1950s. The following decades brought a growing interest in diving activities and a rising number of diving schools and clubs. Whilst Malta has today established itself as a diving tourism destination, responsible access to underwater cultural heritage sites was not always entrenched in dive operations or institutionally recognized. The protection and management of underwater cultural heritage has recently been firmly established within Heritage Malta, the national agency for museums, conservations, and cultural heritage. This paper is intended to outline the trajectory of Malta’s underwater cultural heritage management and to present the innovative and state of the art public access system that is managed by the Underwater Cultural Heritage Unit within Heritage Malta.peer-reviewe

From Discovery to Public Consumption: The Process of Mapping and Evaluating Underwater Cultural Heritage in Malta

The in situ promotion and preservation of underwater cultural heritage sites is one of the main ideas of the UNESCO Convention on the Protection of Underwater Cultural Heritage. Currently, most shipwrecks are found in water shallower than the 50 m contour. The continued technological advances and increases in technical diving and deep-water exploration point towards a shift in this statistic, which is set to increase exponentially in the not-too-distant future. Thus, it is imperative to look at ways in which such directives can be implemented. This paper will highlight the synergy between existing remote sensing technologies and the management of underwater cultural heritage with examples of on-going research projects, such as Malta’s approach to surveying and implementing a scoring system for historic wreck sites based on local and global considerations of historic and natural conditions of site elements. Such an approach allows for the scaling of sites based on a number of parameters and provides instructive information for the creation of management strategies. The intention here is to demonstrate how large-scale remote sensing surveys can make major contributions to site management, which, in turn, facilitates the decision-making process in terms of how and what information is transmitted to divers and members of the public

When Time Is of the Essence—Recording an Underwater Excavation at 110 m

Underwater archaeological excavations present unique challenges, particularly when conducted at significant depths where divers face limited time on the archaeological site. Traditional methods of recording excavation progress, such as manual documentation and drawings, are too time-consuming when the time on the site totals no more than 12 min. To address these limitations, this paper introduces an innovative approach for daily recording and observation of underwater archaeological excavations using 3D photogrammetric models and point of view (PoV) cameras developed specifically for the excavation of a shipwreck situated at a depth of 110 m. The proposed system leverages advancements in photogrammetry and 3D modelling techniques to capture and analyse detailed visual data of the excavation site on a daily basis. Three-dimensional photogrammetric models offer a comprehensive and easily accessible representation of the excavation site, enabling the team to record and analyse excavation levels and features in a highly precise and detailed manner. By comparing the 3D models captured on consecutive days, researchers can precisely measure changes in the excavation area, identify new artifacts or structures, and record the progress of the excavation. The PoV cameras contribute to the planning of daily tasks required on the site. Overall, this paper showcases innovative methods for underwater archaeological excavations at significant depths, employing 3D photogrammetric models for daily recording as well as PoV cameras for observation. The proposed system represents a substantial advancement in the field of underwater archaeology, offering a more accurate, efficient, and reliable approach to documenting and analysing excavation progress, whilst also producing results that can be subsequently adapted and applied to other deep water archaeological sites