Holy See (Vatican City) is about 4.6 times bigger than Pentagon.

Pentagon is approximately 0.096 km² (0.037 sq mi), while Holy See (Vatican City) is approximately 0 sq km, making Holy See (Vatican City) 359% larger than Pentagon.
Tip: This to-scale comparison of Pentagon vs. Holy See (Vatican City) uses the Mercator projection, which distorts the size of regions near the poles.
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