Summary of site:
In the area of the Tempo Valley between Drumderg and a point just north of Lisbellaw there is an area of large, generally flat-topped ridges with a north east/south west orientation. The longest is 1.3 km long and they are up to 300 m wide. They form strong features in an otherwise bland landscape. They are breached by a number of meltwater channels 50 to 75 m wide passing between the ridges and Lough Eyes occupies one of these gashes.
The ridges are thought to be terminal moraines from periods when the front of the main ice sheet remained stable, shedding its debris load for a time, in its general eastward retreat into the Clogher Valley. The meltwater channels obviously relate to water flowing down the Tempo River valley, indeed there is a suggestion that the ridges are not truly moraines at all but secondary features resulting from multiple meltwater dissections of a single, huge morainic mound. Only good exposure of the deposits would allow this alternative explanation to be tested.