The lighthouse is placed to 42º 06 ´3 north latitude and 08º 53´ 8 longitude west, to a 30 meters height on the area and 85 meters over the sea level. A white light meets in groups of 2+1 twinkles every 15 seconds on a scope of 35 nautical miles.
The current Silleiro lighthouse was constructed in 1924 substituting the ancient lighthouse that worked for the first time on March 31, 1862. Of the ancient lighthouse even the granite front survives in the first coast line to approximately 800 meters to the NNO, on the sandbars that the end dismisses.
It was inaugurated on August 8, 1924 and it worked jointly with the old lighthouse for one month. The author of the first project was the engineer Ramón Martínez Campos, being reformed later the above mentioned project by Mauro Serret, who directed finally the works helped by the tower-guard Juan Gutiérrez. The works were awarded in 158.254 pesetas (approximately, 950 €!!!).
When the lighthouse was taking 5 months working, in the night from December 21 until December 22, a fire took place in the camera of service due to the fall of an oil lamp on a few cottons soaked in oil. Two tower-guards, and the daughter of one of them, were not capable of extinguishing the fire. One of the tower-guards could flee for the stairs, while other, with his daughter, looked for refuge in the exterior balcony, suffering the three important burns.
In spite of everything and as soon as the fire was extinguished they tried to set to work again the lighthouse with a help lamp in the middle of a strong thunderstorm that night, but it was impossible. In 1932, the electricity substitutes the oil as lighting element. In the beginning the lighthouse works with a 1500 W lamp that later was changed for a 3000 W one.
In 1955 it turns into radio beacon, being able to be identified by the planes up to a 20 km distance.
At present, in addition to keeping on giving service as luminous sign it is a receiving base of two different systems from measurement of the swell and the currents, and it has in addition to a broadcasting station – recipient of the new system AIS of helps to the navigation.
The environment is full of rocks and small bush, but you can gain access to the lighthouse of easy form. He stands out with its colours, white and red, on the green and gray of the nature that surrounds it. Very close to him, there are the remains of the towers of alertness and batteries of cannons which there had, already some years ago, the system of defense of the entry of the Ría of Vigo.