Long and mighty rivers can be found in North Iceland. Some are glacial rivers that come from the glaciers in the highlands but others are formed by many smaller rivers originating in the mountains. The biggest rivers often spread out and flow in many channels through the valleys. Through the years these rivers have been difficult obstacles for travellers but in recent years they have taken on a new role as some of them are used for river rafting. Some of Iceland's most famous Salmon rivers are in this part of the country and there is also good Trout fishing in the area.