Free-standing rock in the parapet to the N of Castro de Negros. The rock is not in its original location, and has been moved to the upper part of the parapet that encircles the N and NW zone of the castro. It may have fallen from its original location on the hillside to its current location, where it is partially buried in the parapet. Height 1.20 m.; width 0.87 m.; 0.65m thick. It is ovoid in shape with a protrusion in the upper part.
This natural bulge in the rock, oriented so that it faces the castro, is framed by different grooves and lines, some of which enclose the rock. A deep half-moon or crescent shaped groove encloses and frames the natural bulge. Beneath this there are four parallel, non-equidistant lines, which go around the rock and turn towards an indefinable motif. To the back of the rock (the part facing north) there are various lines, at least 6, that go around the rock until the part that is buried. The grooves of the carvings are wider and deeper than those of Early Bronze Age petroglyphs.
The nearby presence of an electricity pylon (20m to the N) and a path situated along the ditch of the Castro, which could have been recently reformed due to the erection of the pylon, means that it is possible that the rock could have been moved to its current location by a mechanical digger and that the marks were caused by the teeth of the digger’s bucket when being moved. A number of factors argue against this explanation – the fact that the lines are not parallel (the teeth of the bucket are parallel to each other), that the lines enclose the natural bulge in the upper part of the rock, and also enclose the entire rock, and that some of the lines turn in the direction of the principal face, looking towards the castro, as well as the fact that no other rocks with similar markings appear in the parapet, leads to the conclusion that this rock was intentionally marked.
Various academics were consulted for their opinion: Ramón Fábregas, Professor of Prehistory in USC; Manuel Rey, Director of the Archaeological Park of Campo Lameiro; and Josefa Rey, Professor of Prehistory in USC and Castro specialist, among others, visited the site and concluded that this was a prehistoric carved rock associated with the Castro de Negros. A menhir-idol? A rock marking a territorial boundary? A symbolic carving? ...