My very rough calculation:
Vatican City has an area of 110 acres. That's roughly 4,800,000 square feet. Assuming each immigrant needs roughly 60 square feet of living space, the Vatican should be able to accept at least 80,000 refugees.
I did not consider uninhabitable spaces like, say, a garbage dump. But I also did not consider the Vatican's many multi-level buildings.
I’m no good with math——what would the density per square mile be if 80,000 immigrants were admitted the The Vatican?
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