Eth. FORUM CASSII
a town of Etruria, situated on the Via Cassia, with the formation of which, from its name, it was certainly connected.
It is known to us only from the Itineraries, which place it 11 M. P. beyond Sutrium, between that place and Volsinii, and 44 miles from Rome. (Itin. Ant.
p. 286; Tab. Peut.
) The distinct traces of the Via Cassia enable us to place it with certainty about a mile NE. of Vetralla,
where an ancient church still retains the name of Sta. Maria in Forcassi,
and some portions of Roman buildings are still extant.
The inhabitants migrated during the middle ages to the neighbouring village of Vetralla.
vol. i. p. 245.)