The tunnels — found beneath the pools of Gan Ha-Shelosha National Park in the Beit She’an Valley — carved into soft tufa rock along Nahal Amal, appear to have supplied water to mills that processed sugarcane in the 14th and 15th centuries CE.

The find was first made when infrastructure work in the area exposed five parallel openings in the rock. “Their engineering precision suggested a hydraulic purpose,” said Prof. Amos Frumkin of the Institute of Earth Sciences at the Hebrew University of Jerusalem, who led the research team that made the discovery. “But unlike the open aqueducts typical of the era, these channels were subterranean—an adaptation to the valley’s geology and the brackish nature of the local water.”

Using Uranium–Thorium dating of stalactites formed soon after the tunnels were dug, researchers determined that they were built during the late Mamluk period. The timeframe corresponds with historical records describing the Beit She’an Valley as a major center of sugarcane cultivation and export across the eastern Mediterranean.