Pentapolis (pĕntăˈpəlĭs) [key] [Gr.,=five cities], collective name anciently applied to several groups of five cities. The chief cities of Cyrenaica on the northern coast of Africa (Apollonia, Arsinoë, Berenice, Cyrene, and Ptolemaïs) were thus called from the 4th cent. B.C. to the 7th cent. A.D. Other cities so named were Rimini, Ancona, Fano, Pesaro, and Senigallia on the Adriatic coast of Italy, where the term originated in the 5th cent. A.D. under Byzantine rule and continued to be used until the 11th cent. Other groups called Pentapolis were in Asia Minor and in Palestine.