Jacksonville is about 2.4 times bigger than Charlotte.

Charlotte (map shows its 157 named neighbourhoods; the area covers the whole city) is approximately 807 sq km, while Jacksonville (map shows its 197 named neighbourhoods; the area covers the whole city) is approximately 1,935 sq km, making Jacksonville 140% larger than Charlotte.
Tip: This to-scale comparison of Charlotte vs. Jacksonville uses the Mercator projection, which distorts the size of regions near the poles.
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