Dolmens are the most attractive elements of the megalithic phenomenon. For their construction it was necessary in the first place to locate the raw material, the stone that was going to be used to erect them. In Galician the use of the granite is predominant but it is possible to find schist. For their extraction, natural lines of fracture in the rock were looked for and then small wooden wedges were introduced in them which after being wet, they dilated, helping to the rupture of the stone block.
For the transport of these blocks (Figura 1.) were used ropes and small logs as rollers , and as several studies show, 5 or 6 people were enough to trail along the ground a stone of a ton, and that is the reason why in Galicia it is likely that our biggest dolmens could be erected with the help of 30 or 40 people.
Once the stone blocks were put in the right place, some ditches were dug, putting the extracted earth around them to use it as a ramp. The first stone to be erected was the head stone, that is to say, the one facing the tomb entrance (Figura 2.). It sloped inwards and it was buried until a third of its size protecting it with small stones and after the remaining stones of the megalithic chamber were leaned on the head stone successively in what is known as the overlapping technique.
Then the barrow was ready to be finished (Figura 3); it could be covered with a protection, a stone layer put carefully in order to prevent erosion and an outer stone ring around the barrow to prevent it from crumbling, and also filling the interior of the burial chamber or propping it up with trunks to avoid its fall, making more sure the dragging and placing of the capstone.
Lastly the interior of the funerary chamber was emptied for the internment of the bodies and the placement of the grave goods (funeral offerings). In later reuses other funeral practises as cremation or secondary burials have been observed.
In Galicia, peasants used to think that the dolmens had been made by the mouros (mythical beings).
The passage grave, when existing, was raised vertically following the same technique and in front of it the ground was flattened forming an atrium bordered by a row of idols (Figura 4.) to indicate the access to the burial chamber.
In Galicia, like in other regions of the European Atlantic façade have been described wooden chambered tombs and it is likely that the remains observed in the village of As Pontes de García Rodríguez belong to such a dolmen although it has not been kept in its original location; of others we only know their archaeological trace that can be observed in their excavations.