The site of Kercado, in Carnac, is situated above the valley of Kerloquet and the ria that runs along the beach of Kerdual for 2 km. It comprises a probable low mound, the cairn of Mané er Groez, with a passage grave, and a curvilinear enclosure of about thirty standing stones bordering the south side of the site. Three orthostats in the passage, three other stones in the funerary chamber, as well as the cover slab, bear engraved signs recorded mainly between 1866 and 1927. In addition to the well-known “axe-plough” on the ceiling of the chamber, we can now add a new inventory of engravings, including pairs of polished blades, a ring, bows, boats with crew and variations on the quadrangular symbol. The aim of this article is to present an updated account of this corpus of engravings, and to take slab morphology into consideration, as well as the anomalies that can obscure our perception of these symbols, in order to enhance our understanding of this passage tomb.