Can I visit the actual house or plot shown in Griffith's Valuation today?

Often the plot can be found, though the house on it may not be the house in the valuation. Use the map reference from the entry on AskAboutIreland and the slider that fades between the valuation map and the modern map, then check the spot against Tailte Éireann mapping and a modern road map before travelling. Field boundaries and lanes survive in many townlands, while houses were rebuilt, extended or let fall. The land is almost always private and usually farmed. View from the public road first, and if a closer look matters, call at the nearest house, say plainly why the place matters to the family, and accept the answer given. Permission asked politely is granted often; it should never be assumed.

Useful pages: The Irish surnames map · Trace your Irish roots · The 1926 Census guide · Coming home · Irish around the world · Plan your journey

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