Once his son reported the find, Mr Le Quesne, a professional archaeologist, fetched a snorkel and dived down to investigate. He discovered fluted columns, 90cm in diameter, on plinths, which appeared to form part of an ancient Greek or Roman temple, basilica or major public building, similar to those at other archaeological sites around the Mediterranean.
On a clear day, the columns are visible from the surface of the water, but it appears that the remains, which include ancient pottery, have stayed untouched for thousands of years.
Michael said: “When I first swam out, I thought they were just rocks, as most people would, but then I noticed that they were cylindrical and knew that they couldn’t be natural, so I called my dad over.
“I’ve been dragged around a lot of ancient ruins, so if it hadn’t been for that I wouldn’t have looked twice.”