Index
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Centre de Restauració de Béns Mobles de Catalunya
INNOVATION & RESEARCH
SÍLVIA LLOBET
Conservation and restoration work on the antechamber of the Mithraeum THE MITHRAEUM IS A LARGE BUILDING constructed between the 2ND and 3RD centuries and divided into different spaces. First, there is an entrance corridor followed by an antechamber meant as a reception area and place to prepare the ritual banquet. This antechamber leads to the cave where the initiation rites and banquet were held, which reflected the architectural features of these spaces of worship: rectangular layout, central corridor and two benches built into the walls where participants could recline while eating. Lastly was the three-part worship room, only the foundations of which still remain, although it must have been presided over by an image of Mithra’s ritual killing of the bull. Background Most of the structures of the Mithraeum were excavated between 2004 and 2005, and since then several urgent campaigns have been conducted, primarily focused on bevelling the wall claddings of the antechamber and the benches in the cave. Given the endangerment of conserving the remains, in 2019 the Centre for the Restoration of Artefacts of Catalonia (CRBMC) and the National Archaeological Museum of Tarragona (MNAT) decided to undertake the conservation and restoration of this sector via the antechamber. The antechamber, the Mithraeum’s reception area This is a trapezoidal area measuring 29 m2. The northwest wall was the facade visible from the portico, and it was built with a baseboard of irregular stones attached with clay mortar and raised with sun-dried brick, then covered with a mural both inside and outside. The remains of the wall that is still conserved inside show a baseboard with a white background and red stripes that delimit a series of panels.
RESCAT
The northeast wall, which was only visible from the inside, is also amidst pillars made of more regular stones attached with lime mortar. The remains of the murals also have a white baseboard and red stripes which delimit panels and inter-panels with an ochre background. Finally, a bench around 60 cm wide runs along the walls, although it is currently only conserved across from the door leading to the cave, and wall claddings are conserved which largely echo the decoration of the others. State of conservation The antechamber’s overall state of conservation was poor. There were numerous agents of deterioration, as the structures are exposed to climatic agents, most importantly rainwater. The site stretches along the western slope of Cap Roig, which projects westward to create a regular platform, where the central core of the villa was located. It spread along a slope until connecting with the southern baths via a ambulatio, to the south of which the Mithraeum was built. The Mithraeum bears the impact of the water runoff, which causes scouring problems on the claddings and the deterioration of the walls’ foundation. The lack of a roof over the structures also led to the development of biocolonisation, such as the growth of plants on top, microorganisms and the damage caused by the presence of insects and other arthropods. Likewise, the exposure to ultraviolet radiation affects the conservation of the murals. The walls, especially those built with clay mortar, had structural problems such as the loss of the mortar and the shift and flaking of some elements. Problems of fissures, flaking, gaps and separations between layers and disaggregation were found on the walls. On the claddings of the Mithraeum, an accreted layer was identified which was analysed in
