The man, who is in his thirties, was taken to Hull Royal Infirmary after he was discovered unresponsive on Peasholm Road near to the seafront in Scarborough in the early hours of Sunday morning.
North Yorkshire Police are now investigating to find out how he came by his injuries.
The road was closed between Peasholm North Marine and Victoria Park, while officers work at the scene to establish the full circumstances surrounding the incident.
Anyone who was travelling in the area late Saturday night, early Sunday morning, is asked to contact police.
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