Esker (Irish: Eiscir ), is a system of ridges that stretch across the middle of Ireland, between Dublin and Galway.
A large remnant of an Esker exists in the Garbally/Ballinamona region of the area giving the townland of Esker its name, Eskers take the form of relatively low-lying ridges composed of sand, gravel and boulders; deposited by water flowing beneath a glacier; that became exposed when the glacier melted at the end of the last ice age, around 10,000 years ago. The Irish name ‘Eiscir’ provides an indication of the significance of the eskers, ‘Eiscir’ meaning ‘divide’. The eskers have become a valued source of building material, with sand and gravel extraction being commonplace. However, the negative environmental impact of such operations is now being realized and this, along with a developing awareness of the ridge’s natural beauty and its significance in Ireland’s history, has led to increasing restrictions.
To this day, the Esker Riada continues to serve as a highway, the main N6 Dublin to Galway road still closely following it; and much agricultural activity still takes place along its length. Indeed, Offaly County has moved to give the ridge protection in its County Development Plan, and has gone so far as to press to have the Esker Riada recognized as a World Heritage Site.