The discovery of the tomb of St. James in the early IX century and the subsequent lifting of the cathedral, caused these watchtowers arise to defend the Arosa estuary, and Compostela, from attacks by Normans and Vikings. Built on the island formerly known as A Figueira, in time of Bishop of Compostela Sisnando I, in the early Middle Ages and subsequently repaired by Archbishop Gelmírez.
Through bonfires are warned of the arrival of pirates to the estuary. The Tower of A Lanzada warned, the Tower of San Sadurniño referring the signal to the Tower de Cálogo in Vilanova de Arousa which in turn made him reach the West Towers in Catoira, putting on alert and defense at all the region and Santiago de Compostela.
The fort would be destroyed by the rebels Irmandiños, and again rebuilt by Gómez Sotomayor until completely fall into disrepair.
This defense against the attacks of the Vikings and sarracenos peoples earned Cambados to be named “Most Loyal Town” by King Fernando II in the XII century, then started a period of splendor that is reflected in the many stately homes that exist in the municipality.