This hammered silver antoninianus coin was stamped during the first part of the rule of Philip I, when his son, Philip II, was Caesar. The coin depicts Philip II, son of Philip I - sometimes known as Philip the Younger. Philip I built many new reservoirs to address water shortages in Rome and he presided over the empire for its 1,000th year anniversary, organizing events at the Circus Maximus, a stadium at which large events were held for the public.