These were published and are more easily acessible in the published form. Edited by Michael Herity, they were published by Four Courts Press, Dublin, in 2001.

This is the original letters – handwritten. The Ordnance Survey Letters are the surveyors’ field notes, commentaries and correspondence to the Ordnance Survey headquarters in Dublin. They were written between 1834 and 1841. The Letters’ collection is commonly known as O’Donovan’s Ordnance Survey Letters, after the historian, John O’Donovan (1806-1861), who led the project of information collection, notation and compilation. The collection provides a unique glimpse into everyday life in many parts of Ireland in the years leading up to the Great Famine. The Letters provide the surveyors’ experiences of the places they visited and their accounts of the local history, topography and antiquities of each parish. Also included are their informal reflections on the living conditions and impressions of the local people in the parishes visited.