In the Middle Ages, records show that King Alfonso II provided the church with this island which is located on the sea-river route to Santiago de Compostela. Later, in the 14th and 15th centuries, when Galicia was a sea of conflicts and was devastated by the Black Death, the Shrine of Cortegada was the venue of major pilgrimages. From 1526 onwards the island was given a regional charter by the church and an isolation hospital set up there. The people that came to the island established themselves close to the dock, and also the hermitage in honour of Our Lady of Miracles and the hospital. With the economic decline of the estuary in the 18th century, the councils of Vilagarcía de Arousa and Carril decided to gift Cortegada to King Alfonso XIII as a summer residence, and thus reinvigorate the local economy there. The legal process took several years to become definitive, and in 1910, when the deed was provided, the Palacio de la Magdalena was already under construction, in Santander. This meant that Cortegada was left without a population and was subsequently put into the hands of the State. Because of its great natural and cultural wealth, in 2002 it became part of the Illas Atlánticas National Park