 Indeed, the oldest known forms of the Latin alphabet itself of the 7th to 6th centuries BC, in the Duenos and the Forum inscription, still write "r" using the "P" shape of the letter.The Lapis Satricanus inscription shows the form of the Latin alphabet around 500 BC.Here, the rounded, closing Π shape of the "p" and the Ρ shape of the "r" have become difficult to distinguish.