But generally you're right, if you zoom out on the population density map, there simply isn't that level of distributed population Central Europe as anywhere in the United States. Europe is more similar to parts of India, China, and West Africa/Nigeria. It looks like the US most closely matches parts of Eastern Europe or Western Russia, but the US cities are substantially more suburban and "fuzzy". Aside from the stark difference between Kiev and Atlanta, in terms of population density the Eastern US seems most similar to Ukraine.
Comparing Sydney to San Francisco and London at the same zoom levels is fascinating (to me) and trying to find other areas on the globe as sparse as the dark bits of Australia is also fun...
It would be neat to see the gradient magnitude of the density of base stations, as it might be a measure of a country's degree of urbanization?
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Edit: Turns out it's not that hard to find areas of 0 base stations near major cities.
That gives me 160k entered over Sydney (Canberra up to Tamworth approximately), 124k over Melbourne, and places/areas of single digits are easy to find in the outback. It also gives me 300k entered over San Francisco, and 1.2million over London. (with easy to find spaces of zero in north Africa).
I'd like to see these figures compensated for population numbers. There's probably 7 million people in my "Sydney" footprint, I'd bet there's 10+ million in the SF/Bay Area footprint, and probably 30million in that "London and the entire south of the UK" footprint.