The Edaga Arbi Glacials fill the bottom of north-south oriented valleys, that were carved by glaciers, into the Precambrian basement and in Early Palaeozoic sediments. These valleys were often several kilometres wide and tens of meters deep. Indeed, northern Ethiopia was glaciated in the Early Palaeozoic (Late Ordovician; ~445 Ma), and in the Late Palaeozoic (Carboniferous-Permian; ~300 Ma). This has led to the presence of glacial sediments as well as erosional landforms in eastern Tigray. Over the last 30 million years the Ethiopian Highlands have been uplifted and the Edaga Arbi Glacials have been exposed as a result of the erosion of overlying rocks. This is one of the few places in the world where the Palaeozoic glacial deposits are well exposed and can be easily accessed.