It's a "structure" built by a sandworm that lives in a U-shaped burrow. It is called scientifically: Arenicola.
Lucky to find a sea anemone. When I poked at the sand nearby, it moved to bury itself deeper into the sand, and only left the tips of its tentacles on the surface.
A log exposed on the beach.
There is still something green in the mix of sand and mud.
A remains of a cow.
And some of the landscapes where the pictures were taken by myself.