The center of Gamla Stan is Stortorget square. This square has a sad history. Christian II killed more than 80 of the leading members of Sweden and buried their necks in the well. This is called the Stockholm massacre. In this square, there are Nobel Museum in one side and buildings built from 13th century to 19th century. Also, a lot of shops are placed in narrow alleyways. Up north from the square, the stock exchange built in 1776 and the Sweden Academy headquarters which selects the Nobel Prize winner are located.