(Arbon) Thurgau, Switzerland.
Roman fort on the SW shore of Lake Constance,
about 30 km W of Brigantium (Bregenz). Mentioned in
the Antonine Itinerary
(237.5, 251.3), the Not.Dig.Occ
(35.34), Amm. Marc
. (31.10.20). Arbor is the first station on the Rhine-Danube highway E of the Raetian
border at Ad Fines. A large fort was built here, probably under Diocletian, on a peninsula in the lake. In the
4th c. a military flotilla, a numerus barcariorum, was
stationed at Constance or Brigantium, and Arbor is strategically located midway between them. The fortress was
occupied probably until the late 5th c., towards the end
by the Cohors Herculea Pannoniorum. Some remains
were visible until the 16th c., and since the late 19th c.
the vicus, its cemeteries, and parts of the fortress have
Little is known of the plan and buildings of the settlement. In antiquity the fort at the tip of the peninsula lay
on the shore, but today it is a short distance inland. It was
surrounded on three sides by the lake; the fourth must
have been protected by a rampart and ditch, now under
the modern town. The fortress, adapted to the terrain,
had an irregular plan (ca. 150 x 65-80 m, area 1 ha).
In the N part a mediaeval castle was built on the Roman
foundations and walls, and to the S a church of St.
Martin and a chapel of St. Gallus. The walls, which have
been partially explored, had towers of various shapes
both at the corners and on the sides: rectangular, semicircular, or segments of circles. Above the foundations
the walls were 2.6 m thick, but 2 m towards the lake.
The remains of one SW tower are preserved to some
height. The interior of the fort has not been completely
explored, but the church of St. Martin may be built over
a 4th c. sanctuary as in Tenedo and Castrum Rauracense.
A church and a Christian community inside the walls are
attested in the Vita Sancti Galli. The museum is in the
F. Staehelin, Die Schweiz in römischer
(3d ed. 1948) 313, 323, 597; E. Vonbank, “Arbor
Felix, zu den Ausgrabungen 1958-1962 in Arbon,” UrSchweiz
28 (1964) 1-24PI
; id., Jb. Schweiz. Gesell. f.
51 (1964) 107; H. Lieb & R. Wüthrich,
Lexikon Topographicum der römischen und frühmittelalterlichen Schweiz
1 (1967) 20-22.
V. VON GONZENBACH