km S of Milan and 11 km S of the Po, it controls the
route across the Po to Ticinum (Pavia) on the other
side. It is famous as the town of the Celtic Anamares
where the Republican general M. Claudius Marcellus won
the spolia opima in 222 B.C. by slaying Virdumarus, the
king of the Insubrian Gauls, in hand-to-hand combat.
Shortly afterwards the poet Naevius celebrated Marcellus' feat in an historical play entitled Clastidium. After
Marcellus' victory the Romans planned to use Clastidium
as one of their chief bases for the conquest of the neighboring parts of Liguria and Cispadane Gaul, but they
had to wait until after the second Punic war (218-201
B.C.) before they could carry out their program since at
the very beginning of that struggle the town was betrayed
into the hands of Hannibal (Polyb. 3.69 and Livy 21.48
32.29,31). When the Romans finally brought Clastidium
under control after 200 B.C., they made it a dependency
The Roman town was in the part of Casteggio known
locally as Pisternile, but no Roman monuments have
survived there. There are, however, remains of Roman
bridges over two neighboring creeks, the Rile and the
Coppa, and there is also a large block of ancient masonry
at nearby Masone, the so-called Fontana di Annibale.
Roman inscriptions, coins, pottery, glass, and architectural fragments have been found at Casteggio in some
quantity. The Municipio houses a few of the finds, but
most have been sent to the museum of antiquities in the
Castello Visconteo at Pavia, 20 km to the N.
The great Roman highway from Dertona to Placentia,
the Via Postumia, served Clastidium; remains of its road
station were found on the E outskirts of the modern town.
G. Giulietti, Casteggio: Notizie Storiche
(1890); M. Baratta, Clastidium
E. T. SALMON