grianan of aileach, ancient drystone ring fort, located on top of greenan mountain in inishowen, co. donegal, ireland

aerial landmark landscape lough swilly meadow nature orbit panoramic ring ruins rural scenery scenic site stone temple sun structure palace tourism tourist travel view iron age irish ireland inishowen peninsula aileach ancient architecture building europe derry greenan ely cashel god gaeltacht grass fort wild atlantic historical county donegal flyover green concentric wall grianan hill drone circle