The property includes four archaeological sites located in the Diquís Delta in southern Costa Rica, which are considered unique examples of the complex social, economic and political systems of the period AD 500–1500. They contain artificial mounds, paved areas, burial sites and, most significantly, a collection of stone spheres, between 0.7 m and 2.57 m in diameter, whose meaning, use and production remain largely a mystery. The spheres are distinctive for their perfection, number, size and density, and placement in original locations. Their preservation from the looting that befell the vast majority of archaeological sites in Costa Rica has been attributed to the thick layers of sediment that kept them buried for centuries.
Spis treści
Brief synthesis
The serial nomination of four archaeological sites (Finca 6, Batambal, El Silencio and Grijalba-2) located in the Diquís Delta in southern Costa Rica illustrates a collection of unique stone spheres located in chiefdom settlement structures of the Precolumbian period. The four sites represent different settlement structures of chiefdom societies (500-1500 CE) containing artificial mounds, paved areas and burial sites. Special objects of wonder and admiration are the distinctive Diquís stone spheres, which are rare in their perfection of large-sized (up to 2.57m diameter) spherical structures but are also distinct for their number and location in their original positions within residential areas.
Criterion (iii):
The illustrate the physical evidence of the complex political, social and productive structures of the Precolumbian hierarchical societies. The chiefdoms which inhabited the Diquís Delta created hierarchical settlements expressing the division of different levels of power centres, presented by the different serial components. Likewise, the exceptional stone spheres, which continue to leave researchers speculating about the method and tools of their production, represent an exceptional testimony to the artistic traditions and craft capabilities of these Precolumbian societies.
Integrity
The four property components contribute specific elements which allow for the understanding of the chiefdom settlement structures. Finca 6 is the only site retaining stone spheres in linear arrangements, Batambal is the only chiefdom settlement visible from a far distance, El Silencio contains the largest single stone sphere ever found, and Grijalba-2 site is unique for its use of limestone and its distinctive characteristics as a subordinate centre, as opposed to the Finca 6 site, which was likely a principal centre. All four sites show to differing degrees signs of the negative impact of past agricultural development and looting of archaeological sites. However, the material which remains preserved in situ is significant enough to express the different aspects of Outstanding Universal Value.
Batambal site is located in close proximity to dwellings and might be negatively impacted by future urban development. In addition, two large development projects, the Diquís Hydroelectric Dam and the Southern International Airport, are currently being discussed. The State Party has committed to undertaking Heritage Impact Assessments (HIA’s) for both projects and given assurances that it will give full consideration and priority to preventing impacts on the Outstanding Universal Value, if either of the projects are to be implemented.
Authenticity
Previous excavations were limited to test sections and most excavation pits have been reburied following the completion of archaeological recording. As a result, the authenticity of the property with regard to design, material, substance, location and workmanship is satisfactory. A challenge for retaining authenticity of setting is the lack of knowledge of the extent of forest clearance during Precolumbian times, which increases the difficulties in judging sight relations between different structures and landscape elements that contribute to the site’s original setting.
Finca 6 site also contains a collection of stone spheres confiscated following previous looting, the original locations of which mostly remain unknown. To distinguish those stone spheres which are in their authentic locations from those which have been relocated, it would need to be indicated more clearly that these spheres are no longer presented in their original position.
Protection and Management requirements
The four components are protected as archaeological sites of public interest according to Law No 6703 on National Archaeological Heritage. This constitutes the highest possible protection for an archaeological site at national level. In addition, the stone sphere settlements proposed in this nomination received legal protection in addition to the highest national level through Presidential Decree 36825-C, which highlights their intended future status as World Heritage Sites.
The legislation attributes exclusive legal authority over the archaeological sites to the State, represented by the National Archaeological Commission and the National Museum. The legal protection of the four component sites is exemplary and complete. To ensure equally high legal protection of the buffer zones, their integration in the new Regulatory Plan for Osa County needs to be finalized.
The management of the four site components is overseen and coordinated by the National Museums of Costa Rica. This institution is supported by an Advisory Council for this specific task. The State Party submitted a Management Plan in February 2014, which outlines the vision and strategic objectives for site management for a period of up to 6 years. It is envisaged to complete necessary conservation activities at all four component sites and provide visitor interpretation and presentation as well as facilitate future accessibility to the three sites not yet open to the public, Batambal, Grijalba-2 and El Silencio.
It seems essential for the success of the management plan implementation that the financial and human resources required for the administration and management of all four site components will be available to the National Museums of Costa Rica, to allow for site managers and guardians to be present on site. For the future protection and conservation of the it also seems essential that Heritage Impact Assessments are undertaken for any proposed developments which might have the potential to negatively impact the property.