Rolling and curving past hay fields and woods, the distinctively red earth of southern Mississippi crowding the soft shoulders, the GRR passes quickly over the 45 miles between Natchez and the Louisiana state line. You won’t see it from the highway, but just across the Mississippi River is possibly the most significant piece of engineering anywhere along its length: the Old River Control Project. More than mere flood control, the project is designed to keep the Mississippi going down to Baton Rouge and New Orleans, rather than finding a new route to the Gulf via the Atchafalaya River. This actually happened during the 1948 flood, and there are hydrologists who predict it is only a matter of time before it will happen again—a potential economic catastrophe for downstream cities along both rivers.

About 10 miles north of the Louisiana border, an unprepossessing intersection of gas stations marks the turnoff west for Woodville (pop. 1,096), where a lovely old courthouse sits at the center of a green square full of stately old oak trees, and three historic churches line the somnolent streets.

The biggest attraction of Woodville, however, is a mile east of the GRR on US-24, where a small sign along the highway marks the entrance to Rosemont Plantation, the boyhood home of the Confederacy’s President Jefferson Davis. Built in 1810 with wooden pegs holding together hand-hewn posts and beams, the house is surrounded by a grove of live oaks and a large rose garden, planted by Davis’s mother, after which the plantation takes its name.