Final answer:
The canal era's high point ended by the 1870s due to the rise of other transportation routes and changes in river courses.
Step-by-step explanation:
The statement is true. The canal era's high point did indeed end by the 1870s. The decline of canals in the United States was primarily due to factors such as the rise of competing transportation routes, like railroads and steam-powered ships, and changes in the course of rivers. These factors made canals less efficient and cost-effective compared to other modes of transportation.