Data Sources

Viettrace uses open administrative-boundary datasets to show Vietnam province/city boundaries before and after the July 2025 merger.

Current Data

DatasetSourceUse In Viettrace
Pre-July-2025 province/city boundariesOSM-Boundaries, admin level 4The 63-province layer.
Post-July-2025 province/city boundariesOSM-Boundaries, admin level 4, with historic records filtered outThe 34-province layer.
Display province layersOSM-Boundaries data processed by Viettrace scriptsRemoves the Truong Sa overlap from the Khanh Hoa geometry so it does not collide with the offshore-islands layer.
Hoang Sa and Truong SageoBoundaries ADM2Separate offshore-islands reference layer, not merged into the province/city datasets.
Pre-July-2025 district boundariesOSM-Boundaries, admin level 6, normalized with parent-province assignment695 districts visible from zoom 7+ (694 from OSM-Boundaries plus 1 research gap-fill, Hoang Sa District, with geometry copied from the geoBoundaries Hoang Sa reference for parity with the post-2025 Hoang Sa Special Zone). Served as static PMTiles on CDN.
Post-July-2025 ward/commune/special-zone boundariesOSM-Boundaries, admin level 6, reconciled against the official 3,321-unit list3,321 wards visible from zoom 8+. Served as static PMTiles on CDN.

Licenses And Attribution

  • OpenStreetMap-derived data is attributed as “© OpenStreetMap contributors” in the map UI.
  • Hoang Sa and Truong Sa data from geoBoundaries is attributed as “© geoBoundaries www.geoboundaries.org”.
  • Viettrace keeps raw and processed data separate so changes can be audited and traced.

Known Limitations

  • OSM-Boundaries data may not be perfectly accurate in every area.
  • Hoang Sa does not have suitable admin-level-4 geometry in the current OSM-Boundaries export, so Viettrace uses a separate geoBoundaries ADM2 reference layer.
  • Truong Sa geometry from the OSM-derived Khanh Hoa province feature is removed from the display layer to avoid overlap, while the original source data is preserved for audit.
  • The post-2025 ward dataset is reconciled against the official 3,321-unit list; 3 units (Hoang Sa Special Zone, Quang Tri Ward, Luc Hong Commune) are research gap-fills constructed from related source geometries to reach the official count.
  • Pre-2025 Hoang Sa District has no admin-level-6 geometry in the current OSM-Boundaries export, so a research gap-fill copies the geoBoundaries Hoang Sa reference geometry to make the district searchable and selectable in pre mode. This is a UX parity decision, not a boundary correction.
  • A complete pre-2025 commune/ward source is not yet available. The layer will be added when a suitable source or community contribution becomes available.

Update Policy

Boundary, name, merger-metadata, and label-placement corrections should be reported through the issue template with clear evidence, location, and context before data is updated.

Report data issue
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