The islands of the Svalbard archipelago, the largest of which is Spitsbergen, have officially been part of Norway since 1920. This wild, fragile area lies halfway between the North Pole and the mainland. Icelandic texts from 1194 contain the first known mention of Svalbard. After the Dutch navigator Willem Barents visited Svalbard in 1596, whaling and winter-long hunting and trapping were virtually the only human activities here for the next 300 years. Sixty percent of Svalbard is covered by glaciers; plants and other vegetation cover only 6%; the rest of the surface is just rocks. No roads connect the communities on Svalbard—people travel by snowmobile. The archipelago's climate is surprisingly mild, with periods of summer fog. The small amount of precipitation makes Svalbard a sort of arctic desert. Permafrost covers all of Svalbard, which means only the top yard of earth thaws in summer. Because it's so far north, it has four months of the midnight sun (as well as four months of polar night).