The 24 Greek marble columns of the nave are topped by capitals depicting leaves blowing in the wind. The mostly 18th-century frescoes are of archbishops. Marble and mosaics similar to Sant’Apollinare Nuovo originally covered the walls, but these were stripped over the centuries.
Sarcophagi of different eras are in the side aisles — note the prevalence of peacocks, a bird frequently seen in art in the Emilia-Romagna region. A small section of the original mosaic floor is exposed at the rear of the church.