AI Cities Practically Next to Each Other?

I was conquering an AI Germany in my current save file, and I was going to move my navy closer to get better vantage points for my bombers. Then I noticed that there was a gauntlet of two German cities within two tiles of each other. Has anyone else seen this ,or is possibly a bug?

the third one you conquered is also within 2 tiles of one of them. that's odd and possibly a bug, but i've also heard of ways to enable founding cities that close together (not sure if it's a coding thing)

The minimum distance between 2 cities is 4 (3 hex between them), but that only applies if the cities are on the same landmass. In your examples, they're different islands. I believe in this case, the minimum distance is 3.