Ever wonder how to find ancient shipwrecks in deep waters? Turns out you follow the breadcrumbs:
[Ben] Ballard says the Mediterranean seabed probably holds thousands of wrecks from the last few millennia. Still, individual boats are hard to find. In order to discover them, the researchers followed ancient trash trails.Ancient mariners often cast large clay jars called amphorae into the sea after using up contents like wine. So many were dumped that they can be followed like a breadcrumb trail. [“Wayfarers of the ancient world,” Joshua Rapp Learn, NewScientist (9 December 2017)]
Fascinating. They must keep maps of these trash trails, as such data would yield information about trade routes. Nothing obviously out there, though.