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Drone rules and no-fly zones in United Kingdom
Where to check airspace before flying a drone in United Kingdom, and who publishes it.
Civil aviation authority
CAA
Official sources
These point at the authorities themselves rather than at a copy, because a copy goes stale without saying so.
In the app
No zone geometry is bundled for United Kingdom yet. The map links to the official source rather than guessing at it.
Open the map