Helena is about 7 times smaller than Jackson.

Jackson (map shows its 125 named neighbourhoods; the area covers the whole city) is approximately 289 sq km, while Helena (map shows its 6 named neighbourhoods; the area covers the whole city) is approximately 44 sq km, making Helena 15.37% the size of Jackson.
Tip: This to-scale comparison of Jackson vs. Helena uses the Mercator projection, which distorts the size of regions near the poles.
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