The ancient stone structures are located around the beach ridges.
The ancient stone structures are located around the beach ridges, principally on the north and south sides.
It has been described as a smoothly-rounded beach ridge made of gravel and sand.
However beach ridges of sand and gravel formed in various places as the shorelines shifted.
A beach ridge may be capped by, or associated with, sand dunes.
The height of a beach ridge is affected by wave size and energy.
Longshore currents have deposited beach ridges since the for 6,000 years.
In newer locations the team documented the remains of semi-subterranean houses built into the beach ridges.
Marine fossils and old beach ridges have been discovered well inland along the river systems.
It is surrounded by narrow beach ridges and swales.
