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

Holy See (Vatican City) is approximately 0 sq km, while Pentagon is approximately 0.096 km² (0.037 sq mi), making Pentagon 21.77% the size of Holy See (Vatican City).
Tip: This to-scale comparison of Holy See (Vatican City) vs. Pentagon uses the Mercator projection, which distorts the size of regions near the poles.
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