The valley of Jostedalen offers spectacular scenery, mainly shaped by glacial erosion. Glacial faults and fractures underneath the glacier have favoured erosional forces, garving out valleys, hanging valleys, cirques and mountain passes from the old mountainous plain.
The largest glacier in Northern Europe, Jostedalsbreen, 487 km2 , covers the high mountain plateau northwest of Jostedalen. 22 named outlets - "glacial arms or tongues" - flow from the plateau glacier, 11 of these into the hanging valleys running more or less vertically to the main valley, Jostedalen. Hanging valleys are found on both sides and can be seen as bowl-shaped openings high up on the hillsides.
The most famous glacial outlets are Nigardsbreen, Bergsetbreen and Austdalsbreen. More than 30'000 tourists come to see Nigardsbreen each year. The well preserved moraine landscape in front of the glaciers, especially Nigardsbreen, tells us much about deglaciation history.
At Nigard there are many moraines which can be traces across the valley and up the hills on both sides. These have been dated by biochemical dating and found to be from the period called "the Little Ice Age" that culminated about 250 years ago. A detoriation in climatic conditions made the Jostedalen glacier grow, and the outlets surged forward or flowed down the valleys, damaging farms and vegetation, and people's livelihood. Although this was a natural disaster at the time, the event has been extremely useful to the scientists of today when studying the invasion of plants and animals onto virgin land.
The deglaciation history is also better understood thanks to these more recent forms. Very clear moraine landscapes were left, forming a very valuable documentation for scientists. The outmost moraine ridge is called the 1750 moraine, and tells us when "the Little Ice Age" culminated. Today, the Nigard valley, the Nigard glacier and some other special areas such as the Fåbergstølsgrandane are highly regarded, both as scientifically interesting areas as well as objects for environmental protection.