IMAGO / ALAMY PHOTO COURTESY OF THE ISRAEL ANTIQUITIES AUTHORITY

INSIDE THE AQUEDUCT. As the Lower Aqueduct passed under the low ridge upon which ancient Bethlehem was built, the water would flow through this barrel-vaulted chamber where the accumulated sediment would settle to the bottom. The result would have been a clear stream continuing on through the tunnel, out through an opening on the north side of the city, and onward toward Jerusalem and the Temple Mount. Although the tunnel is now blocked, this 1940 photograph by Palestine Mandate antiquities inspector Dmitri Baramki shows the tunnel’s southern entrance when it was still accessible.