According to the archaeological catalog of the municipality of Lalín in 1999, these burial mounds were part of a set of seven, known as "Mámoas da Cruz", of which only three are currently preserved.
"Mámoa da Cruz" (Tumulus of the Cross), where you can perfectly appreciate the earthen mound and glimpse the five orthostats that protrude from the chamber and the moved cover slab. In this slab there is a hole in which it is believed that at some point a cross could have been nailed, hence its name. It was recognized by the Department of Culture of the Xunta de Galicia in 2011.
Coordinates: 42º42'55.4''N 8º01'58.7''W
"Altar do Sol" (Altar of the Sun) name with which the neighbors know it, corresponds to a closed area of ??7 orthostats and presided over by a large stone with two recesses in the form of a circle facing east. It was declared a BIC as an artistic historical monument in 1974.
Coordinates: 42º42'52.5''N 8º01'56.6''W
"Mámoa do Cruce" (Crossing Tumulus), so called because it is right at the entrance junction to Alperiz, on the edge of the road. One of the orthostats that is preserved stands out 1.5 meters high and in it you can see an engraving with serpentine motifs, oriented towards the east.
Coordinates: 42º42'51.5''N 8º01'59.2''W
There are two more burial mounds located in what is known as "Zarra do Canal" that are also preserved.
All of them belong to the Neolithic and were looted, like the majority of those existing in Galicia, after the license granted by Felipe III to Vazquez de Orxas in 1609, to recover the possible treasures that existed inside for the Royal Treasury, although many of them were looted by the peasants moved by the "gold rush" created.
