The Banal Windmill is a building.
upgrade => Smock Mill
This building is an improvement of the Windmill. It therefore requires the latter to be built.
The creation of the Banal Windmill is only possible if the technology Banal Windmill has been enabled in the province.
This building requires 3000 man-days
The construction of the building requires 1 political point, 4,000 gold, 40 wood and 10 stones.
The Banal windmill generates 100 gold income every 30 days. It is necessary to collect these 100 gold manually in order to start another 30 days cycle.