Interactive map of proposed partition areas across the UK using flood-fill on k-NN postcode graph.
View the map: https://freegle.github.io/uk-areas/
- Algorithm: Multi-source Dijkstra on k-NN postcode graph
- Seeds: OSM place data (city/town/village/suburb/neighbourhood with wikidata)
- Cell boundaries: Voronoi tessellation with concave hulls per seed
- Colouring: Welsh-Powell 6-colour graph colouring for optimal contrast
- Coverage: 23,271 cells across the UK, all postcodes assigned
- Cells: 23,271 geographic areas
- Seeds: 23,379 OSM place points
- Postcodes: 1,986,796 UK postcodes assigned to nearest seed via k-NN graph
- Population: PAF delivery counts (72M total across UK)
- Click on an area to highlight it and see population/postcode count
- Toggle "Show area names" to see labels (viewport-aware, only at zoom 8+)
- Toggle "Freegle footprint outline" to see current group boundaries
- Toggle "OSM place seeds" to see the underlying place points
- Areas follow postcode density gaps, not group boundaries—a natural town straddling two groups stays as one cell
- Seed-sparse areas may appear "swallowed" by nearest city
- Seed-dense areas (e.g. central London) may be over-fragmented