A group of teenagers working on an archaeological dig in the village of Ibillin in northern Israel uncovered a Canaanite-era fortress dating back 3,700 years.

The youngsters—who hail from Moshav Alon Hagalil and Kibbutz Hanaton and are spending their summer vacation working on an Israel Antiquities Authority (IAA) excavation—unearthed the Canaanite structure, whose existence was previously unknown, in the middle of an olive grove between Ibillin and Shfaram.

Archaeologist Nurit Feig, who is overseeing the project for the IAA, said that “it could be that the youth who are working with us have uncovered a chapter in the history of the Galilee that we didn’t know about. The wall they found is especially massive, and could have functioned as a wall that protected some ruler or another. It appears that the place was active in the Canaanite period, about 3,700 years ago. This is the first time that we’ve found a fortified structure from that era in this area.”