Second Temple Synagogues
The dating and ubiquitousness of ancient synagogues is the subject of some controversy, e.g. see here. Donald D. Binder has a nice web site surveying Second Temple Synagogues where you can find much information about numerous synagogues and inscriptions. One of the most interesting finds is the Theodotus inscription.
Theodotus, (son) of Vettenus, priest and
archisynagôgos, son of an archisynagôgos,
grandson of an archisynagôgos, built
the synagogue for the reading of the law and
the teaching of the commandments, and
the guest-chamber and the rooms and the
water installations for lodging for those needing them
from abroad, which his fathers, the elders
and Simonides founded