The Basilica of the Holy Spirit is a church of the Arian Bishops and later dedicated to the Catholic cult by Archbishop Agnello. The church today does not look any different from the original. The 16th Century portico is made up of five big arches in the front and by an arch on the northern side which dominates the façade. The ambo is in Greek marble and of the 6th Century and decorated on both faces, two crosses laterally on a globe; in the curved central part there are small fluted columns that form three aedicule with shell and tympanum.