Final answer:
In the 1820s, New York City was connected to the Great Lakes region by the Erie Canal, a man-made water highway.
Step-by-step explanation:
In the 1820s, New York City was connected to the Great Lakes region by the Erie Canal. This canal was a man-made water highway, chartered in 1817 and completed in 1825, which connected the Hudson River in New York City to Lake Erie.This was a significant advancement in commerce and transportation, despite the emergence of other transportation methods like highways and steam locomotives. The construction of the Erie Canal vastly improved transportation and commerce by reducing the cost and duration of shipping goods from the East Coast to the West. Despite emerging technologies like the steam locomotive in the late 1820s, the Erie Canal remained the primary method of transport during this time.
At the same time, other forms of transportation were also evolving. Steam locomotives began to compete with horse-drawn carriages, with the Mohawk and Hudson Railroad introducing its first service with a steam locomotive in 1831, while highway projects like the Cumberland Road were developed, largely sponsored by the federal government. However, for the purpose of this question, it's important to remember that in the 1820s, the key link between New York City and the Great Lakes region was the Erie Canal.
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