In situ preservation as the first option (Rule 1)

The first sentence of Rule 1, “The protection of underwater cultural heritage through in situ preservation shall be considered as the first option” is the core of this rule. The consideration given to preservation in situ by the Convention and its Annex is based on the recognition of the importance of the interplay between the site, its story and its context.

It is the most telling phrase in the whole ANNEX, while at the same time it is certainly the most debated and the least understood, especially in the context of underwater exploration. Such misunderstanding is nurtured by those who do not want any regulation to curtail their interests. They will claim that archaeology is about finding things and that it would therefore be ludicrous to say things should be left in place.

It is certainly true that archaeological research – like any research – is about seeking knowledge and it is even about finding objects in order to do this. This popular image is evidently a simplification of the scientific research process of which archaeological investigation forms a part, but nonetheless the popular image is surely not wrong per se. The fact, however, that finding out things ‘in the field’ is not an isolated endeavour, has fundamental consequences for the organization of archaeological research.

In situ preservation is the first option, because

  • The site of a historic event is authentic,
  • Context defines significance,
  • Heritage is finite, and
  • Many sites cannot be preserved in situ.


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Authorization of activities


The second part of Rule 1 states that "activities directed at underwater cultural heritage shall be authorized...” and stresses two major points. In the first place, it implies that any authorizing entity should consider the first option as pointedly as any operator. Above all, however, it stresses that any prospective activity should be authorized by the competent authority that exists on the basis of Article 22 of the Convention.

This clear reference places any activities directed at submerged archaeological sites within the public domain. Decisions over activities directed at heritage belong to the public domain, as heritage has a unique value for humanity. Competent authorities are entrusted with checking and weighing the considerations involved. Their involvement ensures that any activity is only undertaken for the purpose of making a significant contribution to protection, knowledge or enhancement of underwater cultural heritage, and they impose pertinent quality standards on the envisaged work. The role of the competent authority gains even more importance when the proposed activity involves excavation.

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Purpose of activities


Many sites are yet or have long remained unknown because of the simple fact that until discovery they are covered by soil, by water or by both. Evidently it is only through archaeological investigation and research that such newly discovered heritage can be appreciated and investigated.

Archaeology has developed through trial and error just like other fields of scientific research. The last part of Rule 1 claims that activities “may be authorized for the purpose of making a significant contribution to protection or knowledge or enhancement of underwater cultural heritage.” Today’s crucial understanding that excavation should not be undertaken unless for good reason, was not yet manifest when archaeology first developed one or two centuries ago.

Excavation is not only the most characteristic activity of an archaeologist in the popular image, but it is also the most drastic activity directed at cultural heritage that an archaeologist can undertake. If given careful consideration, and if embedded in the context of wider research and research questions, excavation can be a very creative process, producing new knowledge on past societies, or shedding new light on specific aspects of the past.

At the same time, however, it is also destructive. While carefully documenting and combining evidence as recognized, it also destroys the coherence and context of a site. Although excavation can make the heritage more accessible, it also compromises to a greater or lesser extent the site’s authenticity, the quality that is most respected in experiencing and enjoying a place, in identifying with it, or in terms of commemoration.

Excavation cannot do without research. And yet, even a research excavation misses the evidence that fails to be recognized for its significance by the excavator. Consequently, excavation must be embedded in a wider context of research questions with which the team is fully familiar. An ill-considered excavation can neither be undone nor can its results be amended once the original evidence is destroyed.

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Practical lessons

Lessons of the past are highly relevant. The recoveries of extensive underwater heritage, for instance those of the Vasa and the Mary Rose wrecks, have promoted the appreciation of underwater cultural heritage enormously. They have also suggested that ultimately such recovery would be the appropriate practice in underwater archaeology, while at the same calling attention to the issue of limited capacities. The investments engaged in these projects would be difficult to afford repeatedly. However, this is not the sole reason for which full recovery projects are not necessarily the best option.

Appropriate practice varies significantly, depending on the specific circumstances of each site. Accordingly, wide acceptance of the cautionary approach prevails, promoting in situ preservation, in preference to the recovery of artefacts and in preference to partial or complete excavation of the site.

It will never be possible to preserve all sites in their status quo. This is not just a matter of insufficient funds, limited capacities of heritage agencies, or the limited number of qualified archaeologists. There is a range of processes on site and impacting developments on the immediate surroundings that cannot be stopped.

As not all sites can be protected and managed, a pragmatic choice needs to be made, based upon the assessment of all heritage sites and their archaeological, historical and artistic or aesthetic value. In making a reasonable choice, with regard to the finiteness of heritage resources, as well as the importance of authenticity and context, many sites are being preserved for future generations, including future generations of researchers. In this respect, the importance of inventory cannot be overemphasized.

The lessons learned suggest:

  • Promoting in situ preservation where, and whenever possible;
  • Promoting research related to development-led archaeology.
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Other options


Rule 1 indicates that in situ preservation shall be considered as the first option and that in authorizing any activity, this possibility should be considered first as well.

However, ‘first option’ is not the same as ‘only option’, or ‘preferred option’. Partial or total excavation may be necessary under certain circumstances and preferable for a number of reasons. Reasons may be external, such as development projects for which many sites need to make way. If their character is fully understood, some sites will be considered sufficiently significant to warrant their preservation in situ in spatial planning processes. This is very unlikely, however, to be the case for sites whose existence or significance is unknown or only vaguely indicated until development is well underway. Nevertheless, just as on land, development-led archaeology in maritime and offshore projects presents challenges and enormous opportunities for archaeological research.

Fundamental research questions can be addressed without interfering with sites that indeed can be preserved in situ. Time constraints imposed by development-led archaeology on research call for tight and focused research planning. The cost of mitigation, including such research, can often be considered as integral to the project’s development. In many countries [including those who are party to the European Convention on the Protection of the Archaeological Heritage adopted by the Council of Europe on 16 January 1992 in Valetta], this is regulated by law. However, even if it is not, these collateral costs for society are integral to the project and should be accounted for in the project’s development.  Maritime and offshore projects are often of such a scale that they call for explicit political decisions that should take the public interest in heritage into account.

Another external reason for excavation is the need to secure a site’s continued existence, due to instability of the environment, or due to the fact that stabilizing it would be so exorbitant in cost that in situ preservation would not be the preferred option at all.

However, none of these reasons should prevent considering in situ preservation first. This applies to both the initiator and the authority who considers authorization. Understandably, initiators of projects will defend their interest in excavation. They tend to be very creative in finding and formulating reasons for excavation by amplifying the magnitude of vigorous threats to a site. According to their argument, it is almost invariably best to have the sites excavated. External reasons for excavation should therefore always be complemented by substantive reasons as referred to in Rule 1. Depending on the situation, these grounds can certainly be strong and urgent enough to decide on partial or complete excavation in preference to in situ preservation in the end.

Reasons to decide against in situ preservation are:

  1. There are external factors that are prohibitive, and
  2. There are substantive reasons to excavate partially or completely.

Rule 1 explicitly mentions three overall purposes for which activities directed at underwater cultural heritage can be authorized. These substantive reasons are:

  • a significant contribution to protection, or
  • a significant contribution to knowledge, or
  • a significant contribution to enhancement.

These three purposes are mostly intertwined, but independently each can, under certain circumstances, be reason enough for undertaking an activity directed at heritage. The argument for excavation should be convincing and will mostly include a combination of reasons. In exceptional cases a contribution to knowledge can be enough.

The history of underwater archaeology has seen quite a few examples in which interest for the underwater cultural heritage of a certain type or period, or in a specific region, first arose through an exemplary excavation. Sometimes these were well-planned operations whereas in other instances, they shamefully remind us of the pioneering years in archaeology. Their common characteristic is that long-term preservation in situ was very low on the initiator’s agenda, although at the better end of the spectrum, the operations were certainly undertaken with long-term preservation in mind, ‘in a manner consistent with the protection of that heritage’, to use the phrase as used by Rule 1.

It is ironic that our present concern for the underwater cultural heritage might not have arisen if these pioneering – and sometimes exemplary – excavations had not stimulated our consciousness. In less explored areas and for other types of heritage it can well be argued that exemplary intrusive research or a model excavation will do much to enhance the consciousness necessary for the development of well-considered policies, although with present technology, enhancement of understanding can very often be attained by other than intrusive means.

In exceptional cases, a very good research design, addressing pertinent research questions, can be reason enough to sacrifice a stable site through excavation. However, it is certainly not the first option, and needs to meet the maximum requirements of state-of-the-art archaeological projects.

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