Milling grain to make bread is one of mankind's most ancient activities. This notebook is dedicated to the Castelló d'Empúries Flour Mill, an example of the industrial process used to produce flour, differing greatly from the traditional process employed by windmills. Water power provided by the mill run, the evolution of flour mills, as well as the raw materials, the wheat and the process required to produce flour, serve to provide a highly comprehensive insight into the flour industry