Whether they were carved by an idle fisherman or an expert engraver, a collection of hidden artwork has been exposed in the most unlikely of places.
Difficult to see even when you are looking for them the patterns and pictures that have turned up on groynes at Gorleston are certainly the work of a mystery artist of some talent.
But when and why they were created has intrigued the man who found them, John Spooner.
The former Blundeston prison officer spotted them while fishing and even then wasn't quite sure of what he was looking at.
Having re-traced his steps to take a closer look the 67-year-old has concluded that they are the work of some skill - although some are faint and difficult to make out even when photographed and enlarged.
However there is one clear and striking image among the carvings - an ornate depiction of what appears to be Neptune the Roman God of the sea staring out across the water.
Others show a fish, and what could be a man with a spear.
Mr Spooner of Cherry Close, Bradwell, said he had asked around and not turned up even any anecdotal evidence that they were there, unseen at the far end of the beach towards Hopton.
With Gorleston's beach much built up in recent years they would rarely dip beneath the water line, but anyone would have to look quite hard to see them.
Quite why the mystery artist would choose to create something on the groynes facing out to sea where no-one could look at them was intriguing, he said.
He speculated that they would have had to have been chiselled into the wood after the groynes had been installed but reckoned they would have taken some time to complete, possibly even days.
It is not the first time mysterious carvings have turned up in Gorleston.
In 2003 a so-called runic stone was touted as an ancient relic and archaeologists were called in to identify the find.
But instead of being the work of our Bronze Age ancestors it turned out the design had been created by Barry Luxton from Norwich with a hammer and chisel.
Margaret Ward of Gorleston conservation group Start said she was not aware of any groyne carvings but was keen to find out more.
Do you know anything about the mysterious artwork?
Contact liz.coates@archant.co.uk.
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