300mlk is the landmark dining, fitness and entertainment collection at the corner of Martin Luther King, Jr. Parkway and 3rd Street, in MLK River Park, in downtown Des Moines. 300mlk is a four-story brick building, originally built in 1908. It was the Old Tavern Brewery until 1920 when Prohibition banned the production and sale of alcoholic beverages. It is the only remaining pre-Prohibition brewery building in Des Moines.