Eskers that formed in subglacial tunnels are valuable tools for understanding the nature and evolution glaciers and ice sheets. They record the paths of basal meltwater drainage near to the ice margin. The weight of the overlying ice means that the subglacial meltwater is under high pressure.

How are eskers economically valuable?

Eskers rise above the low-lying tundra to create a dry, windswept environment for plants, animals and humans. In the tundra, eskers can be a major source of valuable aggregate for the construction of roads, runways and other infrastructures.

Why were eskers used as a foundation for roads?

Because of its slightly higher ground, the Esker Riada provided a route through the bogs of the Irish midlands. It has, since ancient times, formed a highway joining the east and west of Ireland. Indeed, its ancient Gaelic name is 'An tSlí Mhór', meaning 'The Great Way'.