Longford County Archives holds two sets of 27 Ordnance Survey sheets covering the county at six inches to the mile. The first was published in 1837; the second shows revisions made in 1913–14.
Surveyors worked across Longford mainly in 1835–36, recording fields, roads, buildings and archaeological features. Their field name books add details that the maps themselves cannot always show.
Put two sheets side by side and familiar ground begins to tell a different story: a new road cuts through a demesne, a settlement grows or a building disappears. Keep the survey dates in mind. A change on paper cannot tell you the exact year something happened.
These maps are historical documents, not walking directions. An old lane shown on a sheet may cross land that is private today.
A useful map-reading method
Pick a specific townland. Find it in the earlier map and note a church, road junction or stream. Locate the same anchor in the later edition, then compare what changed.
Next consult the field name books and Griffith’s Valuation. Record the series, sheet and approximate year when citing the comparison.
When the record seems to disagree
Use modern maps to establish current location, not historic ownership; confirm an old building’s function against contemporary documents and the architectural inventory where possible.
An old road or footpath on a nineteenth-century sheet may no longer be open. Use current access information for any visit.
Plan a visit ↗