Willem Janszoon Blaeu, the famous cartographer, was born in 1571 near Alkmaar. He was the son of a wealthy herring seller. His future was planned to be in the herring trade. To realize this, he moves to Amsterdam to set up a herring. But that turned out to be a disappointment for him. He leaves for Denmark where he becomes the assistant of the great astronomer Tycho Brahe.