The nave's interior is 32.7 m long and 14 m wide. Each side chapel measures 3.8 m by 5.4 m. The interior is decorated with of mosaics as well as alternating red and white marble columns and pilasters. Espérandieu wanted a subtle red that would harmonise with the mosaics and not clash too much with the whiteness of the Carrara marble. Jules Cantini, the marble worker, discovered such a red marble with yellow and white veins in the commune of La Celle near Brignoles, Var. For parts higher up, plaster—i.e. reconstituted marble—was used.