(Ansedonia) Etruria, Italy.
colony on a rocky promontory, rising ca. 113 m above
the sea, on the Tyrrhenian coast 139 km NW of Rome.
It was founded in 273 B.C., on territory taken from
Etruscan Vulci (Vell. Pat. 1.14.7; Livy Per
. 14; Strab.
). Its name was derived from a nearby Etruscan
town, probably modern Orbetello. After the wars of the
3d c. B.C. (Livy 22.11.6
; 27.10.8-9; 32.2.7; 33.24.8-9) it
prospered until an unrecorded event of the 60s B.C. left
it sacked, burnt, and depopulated. Partially rebuilt under
Augustus, it survived as a local religious and festival
center until the second quarter of the 3d c. For a century
or so after 350 the ruins of the forum were occupied by
the center of a large estate.
Excavations (1948-54, 1965-72) have traced the city
plan, the principal buildings, the port, and have uncovered the Arx, the forum, and a number of houses. Unexcavated buildings include a bathing establishment, but
no trace of theater or amphitheater has been found.
The colony's fortifications of massive polygonal masonry still surround the town site. The circuit of less than 2
km had curtains flanked by 18 square towers and was
pierced by three gateways and a postern. The gateways
were of the inner court type with arched outer openings
closed by portcullises and inner gates. The town site, sloping northward, covered ca. 13 ha. Its principal features
were twin summits with a level saddle between. Temples
stood on the summits. The forum occupied the saddle.
Main streets at right angles crossed the site from the
gates and were directed at the forum and temple heights.
Secondary streets ending in a pomerial road subdivided
the site into rectangular and trapezoidal blocks.
The Arx, on the loftier summit at the S angle of the
fortifications, was set off from the city by low cliffs and
walls of polygonal masonry. At a broad opening on the
NE front a main street widened to become a sacred way.
The Arx came to be the seat of a major temple, the
Capitolium (175-150 B.C.) and a minor, of Mater Matuta
(?) (200-175 B.C.). The Capitolium, raised on a high
podium above the terraced altar court, had a facade of
four columns, reached across its full width by a flight of
steps. From a deep, half-enclosed pronaos opened the
three cellae of its prototype. The exterior was decorated
with molded and painted revetments and pedimental
sculptures of terracotta. The minor temple, beside the
approach to the Capitolium, was set on a low podium of
polygonal masonry, and had a single, square ceila behind
its deep pronnos. It, too, was adorned with terracotta
revetments and pedimental sculptures.
Under the floor of the Capitolium, on the crest of the
summit, were found the traces of the augural templum
and sacred pit which celebrated the inauguration of the
colony. Behind the Capitolium, cuttings in the rock have
disclosed the outlines of the first temple on the Arx
(240-220 B.C.), dedicated to Jupiter and torn down when
the major temple was built. A small building, later
erected on the site of its altar court and composed of
atrium, meeting rooms, and kitchen, testifies to the observances of a religious confraternity and to the life of
the Arx during the Empire.
The forum was a long, unpaved rectangle, entered at
either end of the long axis by widened extensions of a
main thoroughfare and at either side of one end by a
secondary street. By 125 B.C. it had been surrounded by
buildings, some of which had already passed through
earlier stages. Its entrance from the center of the town
was now marked by a monumental triple archway (175-150) between twin, public buildings (240-220), having
the form of atria surrounded by shops and offices. One
long and both short sides were lined with colonnades
(175-150), behind which were the older facades, identically tripartite, of shops and offices (240-220). Along
the fourth side stood a row of separate, public buildings.
The oldest of these were the comitium and curia (273-250): a circular amphitheater of steps and a covered,
rectangular hall, facing a bicolumnar monument across
the short axis of the forum. To one side stood a temple,
with its forecourt, similar to the minor temple of the
Arx, and the Aerarium (200-175). To the other stood the
basilica (150-125). Along both sides of the forum ran
continuous pairs of steps, in front of which toward one
end small trees were planted in tub-like, rock-cut pits.
A double row of smaller, square pits across this end
seems to have served to secure staging for various public
The principal buildings along the one side of the forum
were preserved by the Augustan revival of the town,
while most of the ruined shop and office buildings were
sealed off and abandoned or turned into dwellings. Between A.D. 50 and 55 the basilica was rebuilt as an odeum
with seats and a stage. Later a mithraeum was installed
in the basement of the curia. In the 4th and 5th c. the
ruins of these buildings provided a skeleton for the estate
center. One aisle of the basilica accommodated a church.
One of the forum's entrances was walled up to make a
The residential blocks of the colony were terraced
lengthwise according to the slope of the town site. In
each block a row of houses on either side of the median
terrace wall opened on the upper or lower street. Six
small houses (250-200) show the uniform plots and
more or less uniform plans of the early colony. Later
houses, rebuilt on two or more of the original plots, display freer plans and gardens. These plans were not of the
typical atrium type but centered on covered halls or open
courtyards. All the houses brought to light so far were
destroyed before 60 B.C. Houses reconstructed in the early
Empire had similar plans.
The port of the colony lay in the lee of the promontory. It consisted of an outer harbor offshore, connected
by a ship channel with an inner harbor at the end of a
coastal lagoon. The outer harbor was protected by a
mole and outlying breakwaters of large limestone blocks.
The embankments of the ship channel were revetted with
polygonal masonry. Recent excavations have uncovered
a watering dock, jutting into the channel, its fountain
house and quays. Measures for keeping the outer harbor free of sand and for circulating water through the
inner harbor are represented by a flux channel to the
lagoon with flood gates and by a large rock-cut flush
basin fed by sluices.
The finds from the excavations of Cosa are to be
stored and exhibited in an antiqunrium on the site.
R. Cardarelli in Maremma
131-42, 155-86, 205-24; 2 (1925) 3-36, 75-128, 147-213;
F. E. Brown, Cosa I, History and Topography
; id. et al., Cosa II, The Temples on the
(“MAAR” 26, 1960)MPI
; id., “Scavi a Cosa-Ansedonia (1965-1966),” BdA
52 (1967) 37-41MPI
; F. Gastagnoli, “La centuriazione di Cosa,” MAAR
147-65; L. Richardson, Jr., “Cosa and Rome: Comitium
and Curia,” Archaeology
10 (1957) 49-51PI
; D. M. Taylor, “Cosa: Black-Glaze Pottery,” MAAR
25 (1957) 65-193; A. M. McCann & J. D. Lewis, “The Ancient Port of
23,3 (1970) 200-211PI
; V. J. Bruno, “A Town House at Cosa,” Archaeology
23,4 (1970) 232-41; M-T. M. Moers, The Roman Thin Walled Pottery
, in MAAR
F. E. BROWN