This is my feeble attempt to show where the "Sarnau" or causeways jut
out for various distances under Cardigan Bay. Land is shown in green, shallow
water in light blue, and deeper water in dark blue. Sarn Badrig is the largest,
covering a large area north of the Mawddach estuary, Sarn-y-Bwch extends from
the Dysynni estuary, and Sarn Cynfelyn/Cynfelyn Patches can be seen south of
the Dyfi estuary.