It is evident that the lake was of importance in ancient times since many Etruscan and Roman sanctuaries surround the lake. However, in connection to the lake as a sacred place especially the Etruscans are of interest. The Etruscans lived in Italy from approximately 700 BC to the 1st century BC when the Roman Republic was assembled and the Etruscans mysteriously disappeared or perhaps blended in with the Romans. The area around Lago di Bolsena was also inhabited in proto-Etruscan times.
An important aspect of Etruscan religion was that signs of divine power could be manifested trough natural phenomena as mountaintops, riverbeds, ancient groves and lakes. Also, natural phenomena as lightning, thunder and earthquakes were seen as signs from the gods. Not only did the Etruscans build sanctuaries around Lago di Bolsena, they also constructed a remarkably large amount (over 20!) of necropoleis. Necropoleis were cities for the dead in which in some cases rows of tombs were arranged as streets and the tombs were decorated as houses.
The necropoleis, the material culture found at sites surrounding the lake as well as deities that were worshipped at sanctuaries suggest a connection to a cult of the dead. Thus, it is possible that the lake was seen as an opening to the underworld in Etruscan times. Underwater research and discovery of Etruscan offerings in the lake could provide more evidence for this hypothesis. On the other hand, other sanctuaries and deities connect the lake to water and fertility cults. Historical sources have suggested that the myth of the fire-god Volta was established at the lake. However, reliable evidence for this is difficult to find.
Image: Copyright Michele Ricci. Aerial view of Lago di Bolsena with the islands Bisentina en Martana.
Edlund I.E.M., The gods and the place. Location and function of sanctuaries in the countryside of Etruria and Magna Graecia. Stockholm, Svenska Institutet I Rom, 1987.