Inscribed pillar details

I can see Pisa mentioned neat the bottom of the text, but I know no more. It might be that MPIIII (where the M and P might have bars over them) is a date; if I take the P to be an inverted d it could be 1503, but I’m guessing in fact that the pillar is Roman, and dates from no later than A.D.300, in which case any date would not be relate to the supposed birth of Jesus of Nazareth, a Jew from Palestine who didn’t get his own calendar until rather later. The letters are roughly hewn, and there may be traces of pigment or paint in them, although it could also have been the low lighting./p>