42nd parallel north

One minute of longitude along the 42nd parallel is approximately 0.7456 nautical miles (0.8580 mi; 1.381 km).

The 42nd parallel became agreed upon as the northward limit of the Spanish Empire by the Adams–Onís Treaty of 1819 with the United States, which established the parallel as the border between the Viceroyalty of New Spain of the Kingdom of Spain and the western territory of the United States of America from the meridian of the headwaters of the Arkansas River west to the Pacific Ocean.

The parallel passes through the states of Wyoming, Nebraska, Iowa, Illinois, Michigan, Pennsylvania, New York, Connecticut, Rhode Island and Massachusetts, and passes through (or near - within three-tenths degree of latitude) the following cities in the United States: The parallel 42° north passes through the southern end of Lake Michigan and Lake Erie.

Part of the water boundary between Canada and the United States passes south of the 42nd parallel.

The southern tip of the Canadian province of Ontario just barely goes south of it at Point Pelee and Pelee Island, while the southernmost portion of the Town of Essex at Colchester is located below the 42nd parallel.