In the midst of narrow streets in the heart of Stampace, a medieval district of Cagliari, stands the church from where one of the oldest religious celebrations in Italy and the most engaging of the island set out each 1st May, being the Festa di Sant’Efisio. The original building dates back to the 13th-century, constructed over a grotto that opens into the limestone to a depth of nine metres, considered by the local faithful as being the prison in which Efisio was locked up before being martyred and beheaded on Nora beach (303 AD). The church was expanded and modified in 1538, when the oratory was built alongside, perhaps designed by the Piedmont architect De Vincenti, who was working in Cagliari at the time on the restoration of the former Collegio Gesuita di Santa Croce. At the end of the 18th century, new operations conferred the present appearance of the church, typical of the 18th century Piedmontese Baroque style. The reconstruction was completed in 1782.