The Muskingum River has a series of working, hand-operated locks that start above Zanesville at Ellis Dam and extend the length of the river down to Marietta, Ohio, on the Ohio River. The dams were constructed by the Core of Engineers for flood control purposes.
So, to get around the dams, canals were constructed. You leave the river, go down the canal into a lock which raises or lowers your boat to the level of the river after the dam.
The Zanesville canal runs between the southern edge of downtown and the river. I hadn't been down on the canal bank for years -- it's a tree-lined area with big old trees that are already losing their leaves. Great for picnics, walking the dog, duck watching, or just a quiet stroll.