The Killybeg's Coastguard and the Rescue 118 helicopter were involved in a rescue on Slieve League on Sunday.
A Dutch tourist raised the alarm when he came across a lady at the top of Slieve League suffering from chest pains.
The Killybegs Coastguard were soon on the scene as were the Donegal Mountain Rescue Team and the Ambulance service.
After locating the casualty she was air lifted to hospital by Rescue 118 from Sligo.
Her condition is not known.