Local myths related to the 1755 Tsunami at Penafirme (Oeste Geopark, Portugal)

The 1755 Lisbon earthquake was one of the most powerful and destructive earthquakes in European history. It struck on the morning of All Saints Day around 09:40 local time, with an estimated magnitude of 8 to 9 Mw. The initial violent shaking for 3 to 9 minutes, was followed by a Tsunami 1 hour later.  In Lisbon the height of the tsunami waves is estimated around 5 to 6 meters, but in several coastal areas it may have attained over 15 meters. The disaster destroyed the powerful city of Lisbon and had a profound effect on the European Enlightenment, sparking intense philosophical and theological debates about divine judgment, the problem of evil (theodicy), and human rationality.

The higher historical record of the tsunami has been reported at Penafirme, a small locality at the Oeste Geopark, 50 km N of Lisbon. Detailed written descriptions testify the tsunami advance and the destruction of an Augustinian Order convent at the height of 16m and 700m away from the coastline. Around this place, several myths appeared, related to this geodynamic event.

i) Santa Cruz (Holly Cross) – when the fishermen saw the huge wave coming from the sea, they ran away to embrace and stay all together around a big wooden cross, which miraculously saved them.

ii) Frei Aleixo (Friar Alexis) – considered to be the only victim, this monk tried to escape the tsunami, running uphill over 80m, and dying due to exhaustion at the top, where a limestone cross signs the fatality.

iii) Ilhéu Grande (Big islet) – a small islet once existed close to the convent and local people say that the tsunami brought so much sand that it connected it to land.

iii) Quinta da Areia (Sandy Farm) - the sea surged and stopped near this rich coastal farm and two mermaids were dragged ashore; the farm workers burned the younger mermaid and the mother mermaid told them they would never have luck again, up to the fifth generation; the farm quickly declined and has been abandoned, remaining in ruins until today.

All these local stories and myths testify the importance given by local people to remarkable natural hazards, such as a huge tsunami. These myths and the historical importance of the event and the ruins are a vivid reminder of the importance of geodynamic processes in shaping the landscape and the communities’ traditions at the Oeste UNESCO Global Geopark.