City Placement Enabling Tech for Marsh?

[Galadrion]

I have searched through the Civilopedia and the Tech Tree, and I can't find any mention of which technology enables a player to settle a city on a marsh tile. Because of this, I would suspect that this wasn't allowed... except that the Civilopedia entry for the mangrove modification to the marsh terrain states that the mangrove is removed from the tile if an emplaced city on the tile grows to size 6. This strongly implies to me that there is a possibility, somewhere in the game, of enabling marshland settlements.

Just as a suggestion, you might consider adding to the terrain entries in the Civilopedia which technologies or other circumstances convert unsettlable terrain to settlable.

 

[Kakafika]

Some terrains are able to be settled only if they are coastal, maybe marsh is one of these? I agree that a Civilopedia update would go a long way, considering how huge the mod is (I'm about to make a post about Great Farmers placing bonuses ). I imagine it's tedious work to keep it updated

 

[raxo2222]

@Galadrion feature removals by cities has nothing to do with settleability on terrains.
To settle on some terrain you need fresh water.