Civ III really should have been called "Culture" it is that different from Civ II.
I am the Iroquois, circa 300 AD, and I have built a road, mine, and fortress near my border within the boundaries of a large town. The road is at a junction connecting several cities with the rest of my civ; it is also a great invasion route into my civ what with all the hills and mountains nearby. The fortress has been there, garrisoned, for well over a century at least.
The Aztec then, with the always land-grabbing AI settlers, build a town near that border. They must have rush built a load of culture improvements, or maybe the damn AI just was acting weird again - or cheating (as usual).
Despite the fact that I led the Aztec in power, culture, and overall score, the border there FLIPS, moves, and my important road, mine, and garrisoned fortress are now in Aztec territory!
It gets worse.
I am not leaving. The AI wants a war, so be it. I am told by the AI that "my recent movements of troops. . ." will casue a war I will get blamed for!
Yes, the Aztec has the nerve to tell me that I will get blamed for any war. That is even DUMBER as I am superior militarily to the Aztecs.
The Aztec Diplomatic AI borders on the suicidal and will not make peace until it has one town left despite my efforts to end the war - my envoys were not seen, or were insulted. I had a huge army near his capital, and I would have made peace for one little town near my border. No deal! He is losing badly but will only accept a stratight peace treaty! No chance. Next turn he lost his capital and second-biggest city. Smart guy.
Worse still, every time I captured an Aztec capital it moved elsewhere free of charge. (No civil war, of course). This didn't occur in Civ II, thankfully. Having a capital is a big help, but the stupid Aztecs were too far gone for help.
It gets even worse. Five hundred years later I've made contact with the Egyptians on another continent - who never heard of the Aztecs until ten years before I contacted them - and they won't even deal with me, saying, "Not after the deal you broke with the Aztecs"!
I broke no "deal"; there was no "deal". The Egyptians shouldn't even know about it (or care); and no one would hold a grudge for over five hundred years and counting. It likely lasted the whole game - or would have if I didn't end the nonsense then having had enough of the stupid AI.
Firaxis, Culture flipping stinks, cities or borders, and your AI advisors are idiots.
Culture borders should never flip over someone else's improvements, especially a garrisoned fortress!
In reality, a civ's borders are determined by POLITICS, DIPLOMACY, and WARAFRE - not so much "culture". If borders were detrmined by "culture". . . most of Canada would be part of the U.S.
Firaxcis, we need ANOTHER patch.