People living in rural Ireland are very conscious of local townland divisions and their boundaries. Few, if any, will have any doubt about what townland they belong to, and generally they will not be pleased if someone places them in another. The townlands provide the basis of the postal address system in rural Ireland.
What follows is taken, slightly adapted, from E. Estyn Evans' book Irish Folk Ways, (Routledge and Kegan Paul, 1957; reprinted by Routledge, 1989)
Of all the administrative units of different sizes and various origins into which rural Ireland is divided - townland, parish, barony, diocese, [county] and so on - it is the townland which most closely touches the daily life and social relations of the countryman. The townland is his postal address, for individual farms preserve their historic communal anonymity: they still belong to the townland though they have become separate units since the 'town' or cluster has broken up.
The townland names, involving so many land holdings, are legal titles, and their Gaelic names, however erroneously spelt on the Ordnance Survey maps, are fossilized in their forms. Only an [Act of the Oireachtas] can alter them. A glance at any six-inch Ordnance map will reveal the strange names that Gaelic imagination contrived and English scribes corrupted..
There are between 60,000 and 70,000 townlands in Ireland, averaging 325 acres or 1/2 sq. mile, and the average townland population in the rural areas is about 50. In fact their size varies considerably, since they were based on the fertility of the land rather than its acreage, and it seems that many moorland tracts were not divided until fairly recent times, for they were formerly shared as common summer pasturage by the people of a whole parish or barony, covering a 100 sq. miles or more. In such hilly areas the townlands may be as much as 2,000 acres; on the other hand in thickly-settled lowlands they are frequently less than 100 acres, and some anomalous fragments of an acre or two are designated townlands.
Irish Folk Ways by E. Estyn Evans