An avoidable tragedy; food was there; just shipped out for profit and to get rid of rabble
By way of update, the myth that the deaths were caused by the potato blight, the "gorta mor" or great hunger resulting, continues. See Archeology Magazine, American Institute of Archeology, Jan-Feb 2013 at http://www.archaeology.org/issues/. At the World Roundup Section at page 22, not delineated at the issue site, is reference to Ireland on the map. The deaths of some 1.5 million people is attributed to the Phytophthora Infestans microorganism causing potato blight. An exhibit at Quinnipiac University, Hamden CT, shows art related to the era -- to be visited to see what causation they trace to the real cause of death. Failure to distribute food, not unavailability of food.
But there was plenty of other food in Ireland, all owned by distant landowners, or local landowners keeping their distance from the locals, and profit-driven.
See http://rootsweb.com/%7Eirlkik/ihm/ire1841.htm. The BBC gives information on whether the famine in Ireland was preventable - food available, but deflected by the powers to England or other places, not to the locals. See also http://www.bbc.co.uk/history/british/victorians/famine_07.shtml.
Skibbereen, a town in the southeast corner of Ireland, was decimated. This is Skibbereen. It was a focal point of the 1840's famine years, and built an extensive memorial. See http://www.skibbheritage.com/famine.htm. A personalized view of the famine is at http://www.eyewitnesstohistory.com/irishfamine. This site offers first-hand accounts, by people at the time.
Skibbereen, Famine Cemetery, County Cork, Ireland
It is hard to know whether a particular ruin is related to the famine. Perhaps this farm was just abandoned with changing property lines. But empty homes and farms haunt fields and towns everywhere.
Abandoned farmstead, ruin, Ireland