The Alcantilado de Montedor Local Natural Monument has approximately 55ha, bounded at north by the Paçô’s Fort and at south by the Camboa do Marinheiro’s Beach. The geological values identified in the area allow us to understand, in high detail, various aspects related to the geological, paleoenvironmental and cultural evolution of the region over the last 400 thousand years. This geosite is the most diversified in terms of preserved geomorphological interests, namely residual, tectonic and coastal. Preserved residual geoforms abound in the form of granite blocks, sinks, tafoni, contact pits and wavy granite floors. At the Alcantilado de Montedor Local Natural Monument we find the most complete record of ancient beach levels in the municipality of Viana do Castelo. It is possible to observe 6 coastal platforms and associated detailed geoforms, such as notches, potholes and P. lividus cavities, which prove the genesis in a beach environment Culturally, this local has saltpans and Engravings from pre-Roman, and the ruins of fishgarths named Cambôa do Marinheiro and Cambôa do Morgado known since medieval times. The geological, paleoenvironmental and cultural history visible in this place, along with the natural beauty of its landscapes, make this geosite an authentic book engraved in the rocks.