Did man-made modifications to Conewago Canal and Tennessee–Tombigbee Waterway assist in navigating these passages?
Conewago Canal The Conewago Canal, on the west bank of the Susquehanna River below York Haven, Pennsylvania, 11 mi south of Harrisburg in York County, enabled late 18th and early 19th century rivercraft to safely bypass rapids at Conewago Falls. Work on the canal of less than 1 mi began in 1793 and was completed in 1797. Robert Morris, a Philadelphia financier, organized the project, which was carried out by chief engineer James Brindley, the nephew of a well-known British engineer of the same name. Two lift locks overcame 19 ft of elevation between the ends of the canal, and a guard lock blocked unwanted water, particularly during floods. Cargo could go upstream as well as down. A boat going upriver could navigate the canal in 37 minutes compared to the whole day it would take 30 or 40 men to pull it upriver along the bank. York Haven is at .
Natchez Trace Trail The Natchez Trace Trail is a designated National Scenic Trail in the United States, whose route generally follows sections of the 444 mi Natchez Trace Parkway through the states of Tennessee, Alabama, and Mississippi. The Natchez Trace Trail is not envisioned as a long, continuous footpath, as is the case with other national scenic trails (such as the Appalachian Trail); rather, only a limited number of trail segments along the route, currently over 60 mi of trail, have been developed for hiking and horseback riding. Moreover, the Natchez Trace Trail, unlike many others that rely heavily on volunteers for trail construction and maintenance, is managed and maintained by the National Park Service. Sections of the trail follow along the Natchez Trace Parkway road shoulder, and cross county and state roads.