The Fox–Wisconsin Waterway is a waterway formed by the Fox and Wisconsin Rivers. First used by European settlers in 1673 during the expedition of Marquette & Joliet, it was one of the principal routes used by travelers between the Great Lakes and the Mississippi River until the completion of the Illinois and Michigan Canal in 1848 and the arrival of railroads. The western terminus of the Fox–Wisconsin Waterway was at the Mississippi at Prairie du Chien, Wisconsin. It continued up the Wisconsin River about until reaching Portage, Wisconsin. There travelers would portage to the Upper Fox River, or eventually, use the Portage Canal. It continued about down the Fox River, following it through Lake Winnebago and continuing on the Lower Fox over 170 feet (50 m) of falls to the eastern terminus of Green Bay. In the mid-19th century, the waterway was improved with numerous locks, dams and canals, including the Portage Canal between the Fox and Wisconsin Rivers. All the locks were not completed until 1876, well after the Illinois and Michigan Canal and at the point where the move from canals to railroads was in full swing. Later development on the waterway introduced barriers to navigation, such as the Prairie du Sac Dam. Use of the waterway was never substantial and it slowly died out. The Portage Canal was closed in 1951 and most of the Upper Fox River locks and dams fell into disuse. The lock system on the Lower Fox River, from Lake Winnebago to Green Bay, was closed in 1983 to prevent the upstream spread of invasive species such as the lamprey. The Fox-Wisconsin is no longer used as a transportation route between the Mississippi River and the Great Lakes. However, the various reaches of the waterway enjoy significant recreational use. Plans are well advanced for reopening the Lower Fox locks and dams. Reaches The Waterway can be divided into four physical reaches: the Lower Wisconsin River, "The Portage" canal and locks at Portage, the Upper Fox River and the Lower Fox River. Physical description Overall the system is about long. It begins in the west at the Mississippi River, rises at a nearly constant rate to Portage, crosses the Great-Lakes/Mississippi River divide at Portage, descends slowly along the Upper Fox to the Lake Winnebago Pool and then plunges in a short reach to the eastern end at the head of Green Bay on Lake