Two walkers were airlifted to safety when they got stuck on a cliff after getting disorientated, officials said.
Belfast Coastguard said a 46-year-old man contacted the emergency services to report his older companion had collapsed with vertigo and needed urgent attention.
A full search operation was launched involving the Ballycastle Coastguard rescue team, Red Bay RNLI inshore lifeboat and a rescue helicopter - R177 - from Prestwick.
The pair were found sheltering at a cliff base at Fair Head.
Two RNLI lifeboat crew went ashore and made contact with the two and administered first aid to the 52-year-old man.
Both casualties were taken into the helicopter, one by stretcher, and were transferred to Coleraine Hospital.
Belfast Coastguard watch manager Steve Carson said the weather was cold at the time but the men were wearing high-visibility jackets and warm clothing.
"We understand that the two men were out for a walk and became disorientated," said Mr Carson.
"Fortunately one of them had a phone on him and was able to get a signal to alert the emergency services.
"Do please check the weather before you set out and make sure you have sufficient supplies if planning an extended trip."