The prehistoric occupation of the islet of Guidoiro Areoso, in the Ria de Arosa, has been known since the late 1980s when work led by one of us revealed the existence of several funerary monuments and a Bronze Age occupation site. In recent years, the erosion has caused a rapid alteration of the dune and the shoreline, exposing a number of new elements and critically threatening the integrity of the sites. As a result of recent coastal erosion and extreme weather events two funerary monuments (Mamoa 5 and Cista 1) and part of the paleosol located in the western coast of the islet have been destroyed. The present paper reports the first results of both the latest survey and monitoring procedures and of the recent study and interpretation of the Bronze Age ceramic assemblages. As a result, the paper highlights the relevance of the islet and of the proposed methodologies for the study of the prehistoric occupation of the coast in Iberia and other parts of Atlantic Europe.