Ptolemy's Map of Ireland (140 AD) is thought to be the first map of Ireland in existence. It was created by Ptolemy who almost certainly never visited Ireland but compiled the map based on military, trader and traveller reports and his own mathematical calculations. Given the creation process, the time period involved and the fact that the Greeks and Romans had limited contact with Ireland, it is considered remarkably accurate. Courtesy of Wikipedia
Further records can be viewed here:
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