There are multiple reasons that a district cannot be built on a tile. Some possible reasons are:

- In order to build a district on a feature or bonus resource, the feature or resource must be removed, which requires a technology.
- Districts and Wonders cannot be built on revealed strategic resources, although they can be built on unrevealed strategic resources.
- Districts and Wonders cannot be built on luxury resources, unless you are playing with the Heroes & Legends game mode. Then you can have Anansi eat luxury resources.
- The tile needs to belong to the city and must be within three tiles of the city center.
- Certain civilizations, such as Gaul, Vietnam, and Māori, have restrictions on district placements.