From the Jerusalem Post:
An ancient rock inscription of the word “Shabbat” was uncovered near Lake Kinneret this week – the first and only discovery of a stone Shabbat boundary in Hebrew.
The etching in the Lower Galilee community of Timrat appears to date from the Roman or Byzantine period.
News of the inscription, discovered by chance Sunday by a visitor strolling the community grounds, quickly reached Mordechai Aviam, head of the Institute for Galilean Archeology at Kinneret College.
“This is the first time we’ve found a Shabbat boundary inscription in Hebrew,” he said. “The letters are so clear that there is no doubt that the word is ‘Shabbat.’”
Aviam said Jews living in the area in the Roman or Byzantine era (1st-7th centuries CE) likely used the stone to denote bounds within which Jews could travel on Shabbat. The Lower Galilee of Late Antiquity and the Early Middle Ages had a Jewish majority – many of the Talmudic sages bore toponyms indicative of Galilee communities.
The Jerusalem Post report continues here and includes a photograph of the inscription. Timrat is located about 4 miles (6 km) west of Nazareth.
The BibleWalks Blog has the story of the discovery, more photographs, and directions to the inscription.