An important place in history, this National Historic Landmark preserves the initial point from which all surveys of property acquired through the Louisiana Purchase of 1803 originated. An elevated boardwalk above the surrounding headwater swamp leads to the granite monument marking the surveys starting point. Wayside exhibits tell the story of the Louisiana Purchase, which opened up the American West. Other panels interpret the lowlands and its native flora and fauna. Restroom facilities are located at the trailhead of this day-use park.