Answer:
The one key difference between the Lancaster Turnpike and the Cumberland Road is that the former runs across only one state and the latter spans at least five states.
Step-by-step explanation:
The Lancaster Turnpike is a paved highway that was built by private entities in 1795, whereas, the Cumberland Road the National Road was built and completed by the government in 1837.
The length of the former is 63 miles. whereas, the length of the latter is 620 miles.