Just minutes from Downtown Washington, DC! The grand MGM National Harbor is a world-class destination resort casino in Prince George's County located at the. The company's building plans at National Harbor are subject to approval by Prince George's County's Planning Board and County Council — a. No hay información disponible sobre esta página. One of the three bidders for a Prince George's County casino site has purchased a acre site in Fort Washington. . On December 20, , the Prince George's County casino license was awarded to MGM Resorts International for a casino resort, which opened on December 8, Plan your vacation to Prince George's County and find hotels, things to do, restaurants and trip planning guides to make the most of your visit. A planned Prince George's County casino could have significantly more slot machines than were authorized by the Maryland legislature when it.