Oops.
My bad.
Thanks.
5.56mm
Don’t apologize! There are 5 more maps going further back at the National Geographic source I posted. You can read up on Crimea history there.
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300 Years of Embattled Crimea History in 6 Maps — National Geographic 2014
Crimea has changed hands many times in its history.
https://www.nationalgeographic.com/science/article/140305-maps-crimea-history-russia-ukraine