Lake Erie is the shallowest of the Great Lakes (averaging only 62 feet) and overall the smallest by volume. Erie is also exposed to the greatest effects from urbanization and agriculture. Lake Erie measures 241 miles wide and 57 miles from north to south, and has 871 miles of shoreline. Because it's not as deep as the other lakes, Erie warms rapidly in the spring and summer and is frequently the only Great Lake to freeze over in winter.
- Lake Erie is the warmest and most biologically productive of the Great Lakes.
- Built in 1822, Marblehead Lighthouse on Lake Erie is the oldest active light tower on the Great Lakes.
- The Lake Erie walleye fishery is widely considered the best in the world.