Holmengrå is the only place in Hordaland where we find traces of the abrasion that is supposed to have transformed Western Norway from a Himalaya-like high mountain landscape during the earth's Paleozoic Era, to a flat lowlands terrain during the Mezosoic Era. Just 400 million years ago, large and small stones plummeted down from the high mountains. Some of these stones became incorporated into the conglomerate bedrock on Holmengrå.
Until 1743 the people from Modal had to wait for a flood in MOSTRAUMEN before they could draw their boats up the river current, and then row back across Lake Movatnet. But, that year the flood opened a free passageway all the way to Mo. Hordaland had gained a new tidal waterway.
The three spades in the municipal coat of arms for Modalen are sand spades. Sand quarrying has brought income and employment. As much as 70,000-80,0000 tonnes of sand and gravel left the municipality each year since the turn of the millennium, to be used as cementing sand. Why is Modalen endowed with so much sand?
Eksingedalen alternates between wide, flat flood plains with good farmland, and narrow passages with waterfalls where the roads cling to the mountainsides. The alternations in the landscape are a result of the sculpturing work by glaciers over several ice ages, and the deposition of the glacial river deposits when the last glacier finally melted back.