Despite being rich in later prehistoric and historic archaeology that includes megalithic monuments, Bronze age copper mines and medieval castles, the Mizen Peninsula, south-west Ireland, has revealed little about its stone age past. Evidence for a Mesolithic presence in SW Ireland is rare and, to date, all archaeological finds of this age in Co. Cork are further north and east of the Mizen Peninsula. However a recent palaeoecological study of pollen, non-pollen palynomorph, plant macrofossil and microscopic charcoal data from a peat bog located near Mount Gabriel has provided evidence for disturbances, characterised by fire disturbance of woodland and exploitation of wetlands, since ca. 8400 years B.P. Two working hypotheses are considered to explain these disturbances: human activity or natural agencies. If the human activity hypothesis is accepted, they represent the first possible evidence of a Mesolithic presence on the Mizen Peninsula.