This route begins and ends at the Lighthouse of Punta de Mera, guide to the entrance of the harbour of A Coruña and also an old defensive post. It consists of two towers of 11 and 14 metres in height respectively, their beams of light reaching heights of 56 and 81 metres above sea level respectively. From the beach it is possible to see one of the towers, but the second one can only be seen from the viewpoint. They are 300 metres apart and from this site there is a 270º panoramic view of the sea and an excellent perspective of the Ría de A Coruña. This, also called Ría do Burgo, and is included in the Rías Altas within the Ártabro Gulf.
This strategically located coastal area was the site of an old military battery, the battery of Mera. Along with other batteries and the forts of Santa Cruz and San Antón, they are part of the protection structures for the Ría de A Coruña. These forts, built in 1640 and 1655, had no land defences. As a consequence of the First World War several defence plans were carried out in harbours in Spain. Considering Ferrol as one of the most relevant shipyards of the time they proceeded to complete a defensive network for the whole Ártabro Gulf. During the dictatorship of Primo de Rivera in 1926, the Rías of Ferrol and A Coruña became spectacularly protected enclaves. The military ruins in Costa de Dexo correspond to the battery of Seixo Branco, designed before the Civil War.