Sogn Fjord, fjord, western Norway. It is the longest and deepest fjord in Norway, and its mouth is located 45 miles (72 km) north of Bergen. Its length, from the offshore island of Outer Sula (Ytre Sula) in the North Sea to Skjolden, at the head of its longest branch, Lustra Fjord, is 128 miles (206 km). The fjord’s maximum depth is 4,291 feet (1,308 metres), and its main axis is east-west. Its narrow, deep tributary channels extend almost to the Jotunheim Mountains on the east and to the Jostedals Glacier on the north. On the south, Aurlands Fjord extends almost to Halling Mountain. Sogn Fjord and its branches include some of the most picturesque scenery in Norway and form an important tourist area. There is some farming at the fjord heads, where alluvial-soil deposits have built up. There are numerous waterfalls along the fjord, many of which have been harnessed to provide electrical power for industries; the large aluminum-processing plant at Årdal is particularly important.