At Port Royal State Historic Park, the Sulfur Fork Creek serves as the county line between Robertson and Montgomery County. The historic 1887 bridge that crosses that creek was part of the original alignment of the Old Clarksville-Springfield Road. Closed to vehicles, you can now walk across this bridge, but you can't go to far as the park ends soon afterward where you can now see this farmland. The current alignment of the old highway runs to the right of this farm.