St. Victricius found out, and the
church-martyry and the four known basilicas bear witness, that Nis contained many churches
consecrated to different saints (cults), which includes it into the group of towns called Martyriopolis.
Such centers primarily celebrated the martyrs suffered in the very town or its vicinity.
Martyries (marturiums) had been erected above their graves.
The church-martyry is distinguished both by its location
and architectural forms in order to emphasize the martyry with the relics of saints. Niš
was an important religious center at that time.