Pea Ridge National Military Park  The site of one of the largest Civil War battles west of the Mississippi River, Pea Ridge marks the successful culmination of the Union's effort to secure control of the Missouri and Mississippi rivers and protect the arsenal at St. Louis, which made easier the supply of General Grant's Vicksburg campaign. The park encompasses 4,300 acres and includes a seven-mile, self-guided tour with 10 stops featuring wayside exhibits, including Elkhorn Tavern. It also has a visitors center, museum and bookstore