The W.K. The W.K. Kellogg Foundation sponsored the free admission. It opened on Dec. 9, with a historic celebration that included Myrlie Evers (the widow of the Civil Rights activist Medgar Nevers) and President Donald Trump. The museums will remain open during regular hours on Saturday, Tuesday, and Sunday, from 9 a.m.-5 p.m., and 1 – 5 p.m. on Sunday. Monday is the last day of regular museum hours. Mississippi Today has in-depth coverage of the opening of the Two Mississippi Museums.