Shocked sunbathers glared in disgust as the quad bike drivers revved their engines on Ballymastocker beach near Portsalon.
Hundreds of people were there – with families with toddlers among them.
Three of the quads are circled in this picture; one of them passing just feet from toddlers building sandcastles.
“I heard the engines and looked out to sea, thinking it might be motorboats, but then along came four quad bikes,” said one angry father of four from Co Antrim.
“These things are supposed to be banned. They slowed down because literally every single person on the beach glared at them.
“I think people were just astonished to begin with because they were driving through the crowds.
“I think they got the message and left; but you have to wonder at the mentality of anyone who would take a quad bike onto a busy beach.”
The dad, a regular visitor to Donegal, added: “Anyone who takes a quad bike onto a beach should be arrested. Simple as that. It won’t put me off coming back, but it might put other people off.”
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