This is a breakdown of how the barrier acres (BA#) are identified and used in mapping out a town. It seemed to me like there was little information available to this end, so I figured I'd run some tests and take some notes. If you see anything inaccurate, let me know. I think I pretty much got it down, though. Hope somebody finds this useful.

Barrier acre breakdown:

BA0: $00C2 - West 1st level Cliff/wall.
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BA1: $00C3 - West 2nd level cliff/wall.
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BA2: $00C4 - West 1st to 2nd level transition.
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BA3: $00C5 - N/A - Unable to identify. **
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BA4: $00C6 - West 1st level ocean transition.
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BA5: $00C7 - West 2nd level ocean transition.
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BA6: $00C8 - North 1st level cliff/wall.
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BA7: $00C9 - North 2nd level cliff/wall.
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BA8: $00CA - 1st level gate.
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BA9: $00CB - 2nd level gate.
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BA10: $00CC - 1st level waterfall.
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BA11: $00CD - 2nd level waterfall.
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BA12: $00CE - North/West 1st level corner.
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BA13: $00CF - North/West 2nd level corner.
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BA14: $00D0 - North/East 1st level corner.
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BA15: $00D1 - North/East 2nd level corner.
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BA16: $00D2 - East side 1st level cliff/wall.
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BA17: $00D3 - East side 2nd level cliff/wall.
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BA18: $00D4 - East side 1st to 2nd level transition.
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BA19: $00D5 - N/A - unable to identify.**
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BA20: $00D6 - East side 1st level ocean transition.
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BA21: $00D7 - East side 2nd level ocean transition.
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BA22: $00D8 - 1st level open ocean.
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BA23: $00D9 - N/A -Unable to identify.**


**N/A unable to identify: I was unable to figure out what these acres are for. They don't seem to have practical uses, unless I just missed something. If you know, please tell me.