Philadelphia is about 1.7 times bigger than Antwerp.

Antwerp (map shows its 62 named neighbourhoods; the area covers the whole city) is approximately 208 sq km, while Philadelphia is approximately 348 sq km, making Philadelphia 67% larger than Antwerp.
Tip: This to-scale comparison of Antwerp vs. Philadelphia uses the Mercator projection, which distorts the size of regions near the poles.
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