A fascinating and mysterious place, the Saint Efisio prison, included among the itineraries of the underground city, is one of the most important places in the memory of Cagliari's most venerated saint.
That towards Saint Efisio is undoubtedly one of the most deeply rooted cults in Sardinia, carrying on a tradition that lasts more than three centuries and transcends simple religious devotion. This is demonstrated by the fact that his figure was invoked many times in Cagliari's history: from the 'baroque plague' that ravaged Sardinia in the five-year period 1652-1657 to the attempted landing of the French in 1793, to the danger of poisoning Cagliari's waters. In recent times, even the Covid emergency has seen the warrior saint invoked! In short, devotion to Saint Ephisius continues to be a fact that seems to transcend mere legend.
Among the most important places linked to the figure of Saint Ephisius is the so-called prison in which, according to tradition, he was imprisoned and tortured. The 'Passio Sancti Ephisii' gives information about Ephisius' imprisonment, according to which the saint was imprisoned in Cagliari inside a hypogeum cave, because of his conversion to Christianity: here he was tortured and then transferred to Nora, where he was beheaded on 15 January 303 AD.

Located 9 metres below street level, dug into the depths of the rock and accessible via a steep flight of steps that has its entrance from number 34 Via Sant'Efisio, the prison is actually a place full of mysteries.
Recently restored, it has a quadrangular plan and irregular dimensions. Inside, the space is articulated around two pillars spared during excavation, the first of which houses a dedicatory plaque referring to the restoration of the altar. The latter is located in the eastern wall, leaning against a small apse surrounded by "azulejos" dating back to the 17th century, still in an excellent state of preservation. Initial restoration work was conducted by archaeologist Antonio Taramelli, with the main objective of establishing the historical period and continuity of use of the site.
Unfortunately, the state of conservation of the area, combined with the very few material finds, made it impossible to establish a date with certainty, allowing only hypotheses to be formulated. Among these is the idea that the hypogeum was already used in late Punic times as a temple dedicated to the cult of Isis, given the identification of a well dug into the floor, which would have contained mystical waters, propitiatory to initiation rites. The actual antiquity of the site was also confirmed by the discovery of some coins dated between the late Punic period and the 1st century AD. Other scholars claim a use as a repository for the storage of quarry material, perhaps subsequent to the cultic one. It is difficult to say whether those walls somehow housed an early Christian community, later becoming a prison for the faithful and thus also for Saint Ephisius.

During the 17th century, in the midst of the Counter-Reformation, interest in the search for the relics of local saints and martyrs was ignited. Many places throughout Europe were involved in a process of rediscovery of the faith that stimulated numerous excavation campaigns aimed at finding the bone remains of supposed martyrs of Christianity.
Some members of the Arciconfraternita del Gonfalone therefore asked the religious authorities to investigate the hypogeum. The brethren were not looking for the relics of St. Ephisius, buried at the site of his martyrdom in Nora and later transported to Pisa, but those of other martyrs, possible followers of the warrior saint. In 1616, a burial excavated in the earthen floor belonging to the martyr Edizio, a soldier following Saint Efisio, was found.
Even today, more than four hundred years later, the prison of Sant'Efisio remains one of Cagliari's most fascinating and mysterious places, capable of telling a story of faith as well as a deep bond between a martyr and his city.
Roberta Carboni has been a tourist guide and art historian for over 10 years. She lives in Cagliari and is passionate about Sardinia, which she has loved so much, all her life, which is why she has chosen to tell its story through exclusive thematic tours. In this way, she contributes to making the island known not only to those who do not yet know it, but also to the Sardinians themselves. The tours take place both within Cagliari, i.e. in the historic centre and other parts of the city, and in the surroundings of the city, going also to the south and centre of Sardinia.
Participate in the thematic tours created by Roberta Carboni - tourist guide in Cagliari...discover more!
Bibliographic references
Raimondo Carta Raspi, Storia della Sardegna
AA.VV, Sant’Efisio: martirizzato dai romani, santificato dai cristiani, venerato dai contemporanei. Catalogo della mostra (Cagliari, 14 aprile-30 settembre 2018)