Ferentino (anc. Ferentinum), a town of Italy, in the province and 40 m. S. E. of the city of Rome; pop. about 8,000. It is situated nearly 1,600 ft. above the sea, and is surrounded by ancient walls built of hewn stone without mortar. The cathedral is paved with ancient marbles and mosaics. Ferentino is celebrated for its splendid view over the Volscian mountains, for its mineral springs, and for its antiquities. Besides large portions of the walls built in the Cyclopean style of large irregular and polygonal blocks, there are many other interesting remains of Roman structures and numerous inscriptions. The ancient Ferentinum seems, judging from the remains, to have been an important place, although little mention is made of it in history beyond the fact that Hannibal devastated it in 211 B. C. Horace alludes to Ferentinum as a remote country town, but he is supposed to refer to another place of the same name in Tuscany.