Vicksburg National Military Park will commemorate the 150th anniversary of the preliminary announcement of the Emancipation Proclamation at 10 a.m. Saturday with a program ntitled, Contested Freedom: Emancipation, Reconstruction, and the Vicksburg Riots of 1874.

Park ranger Dr. David Slay will conduct the one-hour program on the front lawn of the Shirley House on the park tour road. The program will focus on the 1874 Vicksburg riots and sites within the park related to riots.

Park admission is $8 per car, and limited parking is available along the tour road between the Shirley House and Illinois Memorial.