Photo 1. Glacial U-shaped valley in the hinterland of Gumance above Klana
Traces of the action of bygone glaciers can still be seen today in the current relief of the mountains in Rijeka’s hinterland, a little over 10,000 years after the glaciers began to retreat and melt. One of the more interesting examples in our region is the glacial valley that stretches above Gumance in the Klana hinterland. This glacial valley was formed by a glacier that flowed from Mt. Snežnik (1796 metres above sea level) in Slovenia and melted in the Gumance region, depositing thick layers of the glaciofluvial gravel it was carrying. How do we know that this valley was shaped by a glacier? Similar to other glacial valleys, the valley above Gumance has a pronounced U-shape, indicating that ice once flowed through it, breaking off parts of the rock from the valley’s sides and bottom, and making the valley deeper and wider until it got the distinctive shape of a glacial valley. Unlike U-shaped valleys carved out by glaciers, valleys created by the cutting action of streams or rivers typically have a V-shape.