Final answer:
The passage describes a river route, specifically the Ohio and Mississippi Rivers, as depicted by the mention of cities connected by these waterways and the reference to a flat boat.
Step-by-step explanation:
The geographical feature likely being described in the passage is a river route. The passage mentions various cities such as Dover, Covington, Louisville, Henderson, Smithland, Memphis, Vicksburg, and Natchez, which are all connected by the Ohio and Mississippi Rivers. The reference to a flat boat further solidifies the connection to a river route, as flatboats were commonly used on rivers in the past for transport and trade.