The land, described by the Norwegian Poet Bjornson as rising "furrowed and weatherbeaten above the sea," is the most mountainous in Europe and includes about 150,000 island. The Western part of the country is warmed by the gulf Stream and enjoys warm summers and mild winters. The Northern reaches lie well above the Arctic Circle where the sun does not set from the middle of may to the end of july and does not rise from late November to late january. Here the nomadic Lapp tribes tent great herds of reindeer. Norway's people, nearly 4 million in number, enjoy a high standard of living and a comprehensive system of social welfare. Their government is a hereditary monarchy under a constituion, which was 150 years old in May of this year.