The Irish name
Eiscir Riada provides an indication of the significance of the eskers. The first element (and English
esker) comes from Old Irish
escir meaning "a ridge, an elevation (separating two plains or depressed surfaces)" and the second is from Old Irish
ríad which refers to "riding, driving" (later "taming") of the horses or oxen driven on it. Following a battle at
Mag Lena, in the second century, the island of Ireland was divided into two political entities along the line of the eskers – ‘
Leath Cuinn’ (‘Conn’s Half’) to the north, and ‘
Leath Mogha’ (‘Mogha’s Half’) to the south. 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
Irish name is ‘An tSlí Mhór’, meaning ‘The Great Way’. The
Slighe Mhór ('Great Highway') provided a link between
Clonard Abbey,
Durrow Abbey and the monastic settlement of
Clonmacnoise, constructed at the point where the
River Shannon passes through the Esker Riada. In contrast with the surrounding boglands, the glacial sands typical of the eskers provided well drained and relatively good quality land, proving useful for agriculture. ==Present day==