maintained towpath, and nearby private property prevent access during the summer. Fourteen of the locks had Marshall gates, which are unique to the Hennepin, and were raised and lowered on a horizontal axis. Five of the locks have been restored to working condition, although they are not used. One of these is a Marshall Gate lock. All of the gates from the remaining locks have been replaced with concrete walls, creating a series of waterfalls. The Hennepin originally had nine aqueducts – concrete troughs which carried the canal and its traffic across larger rivers and streams. Six of the aqueducts remain while the other three were replaced by pipes that carry the flow under the creek or river which the canal crossed. Geography The Hennepin Canal follows a natural low area between Hennepin and Rock Island. This is actually the ancient channel of the Mississippi River, which at one time flowed from Rock Island to Hennepin, and then south through what is now the Illinois River channel. The Illinoian Stage, about 300,000 to 132,000 years before present, blocked the Mississippi River near Rock Island, diverting the Mississippi into its modern channel. History of the canal The Hennepin Canal was built in order to lower freight prices. Local and government supporters struggled to get it built. The idea to build the canal arose in 1834 (Sage 1). It would allow the shipping of heavy and bulky freight where the railroad could not. The proposed canal would join the Illinois and Mississippi Rivers creating a quick route from Chicago to the Mississippi River. To build the canal would mean that local citizens would have to gain the support of their state and other beneficial government officials (Yeater 2). The canal reduced the distance from the Illinois River to the Mississippi by . Interest in the canal increased during the Civil War, when relations between the Union and the UK were deteriorating to the point where war was possible. If this happened, the St. Lawrence River and Welland Canal would be closed to U.S. ships, and people from the Great Lakes area could not compete in eastern markets. Because war did not occur, many of those who initially supported the project soon lost interest (Yeater 2). The state of Illinois would not allow the canal to be constructed out of its funds; therefore, during the remainder of the 1860s, several legislatures, most notably