You cannot build trade posts in Tunis (and probably some other provinces on african trade route), despite the icon on the trade zones mapmode.
[ HIP Release: 2020-03-19 (Frosty2) ]
EMF: Extended Mechanics & Flavor (v11.1 - 2020-03-06)
Arumba and Internal Tab Shortcuts (2019-05-18)
ARKO Interface (2019-12-18)
SWMH (v3.41 - 2020-03-06)
ARKO Armoiries (2019-12-18)
LTM (C - 2019-12-02)
[ HIP Release: 2020-03-19 (Frosty2) ]
EMF: Extended Mechanics & Flavor (v11.1 - 2020-03-06)
Arumba and Internal Tab Shortcuts (2019-05-18)
ARKO Interface (2019-12-18)
SWMH (v3.41 - 2020-03-06)
ARKO Armoiries (2019-12-18)
LTM (C - 2019-12-02)