The square dates back to 1645 when the Staten van Holland and West Friesland were given permission to expand the city for the fifth time. One of the expansions took place where the Koemarkt lies today. The original square was a flat market field, with vertical poles where cattle could be tied up. In 2009 the Koemarkt was redesigned. With a wonderful work of art from Hans Kuyper and the terraces from the restaurants and bars around the square the Koemarkt is the nightlife centre of Purmerend.