Jyske Ås is a ridge made from glaciers during the last ice age over 12,000 years ago. It is 38 km long and 2 km wide. 39 of the hilltops on the ridge is more than 100 meters above water level and the tallest of them is 136 meters and is the tallest point in North Jutland
Over 15,000 years ago a mighty glacier came from Russia. The ice made its way across the Baltic Sea, over the cliffs of Skåne and Halland in Sweden and down into the Kattegat sea, from where it pushed rocks, gravel, sand and clay, and brought it to North Jutland.
In the eastern part of North Denmark, the glacier stopped, during the year it moved a bit back and forth here, depending on the temperature, but after a longer period of warmer temperatures the ice disappeared and turned into great meltwater rivers. The melting of the ice ended about 12,000 years ago and left was the material from the bottom of the sea.