The Ancient World’s Longest Underground Aqueduct

It turns out the aqueduct is of Roman origin. It begins in an ancient swamp in Syria, which has long since dried out, and extends for 64 kilometers on the surface before it disappears into three tunnels, with lengths of 1, 11 and 94 kilometers. The longest previously known underground water channel of the antique world — in Bologna — is only 19 kilometers long.