OpenSAK can automatically fill in the county, state, and country fields for your waypoints using reverse geocoding. It always starts with a fast offline lookup, and optionally follows up with an online refinement for higher accuracy.
There are two ways to open the dialog, and both open the same window. The difference is the default scope selection:
- Waypoint menu → Update Waypoint Locations… — opens with Only waypoints with missing location data selected by default.
- Right-click a waypoint → Update location data… — opens with Only this waypoint selected by default.
This option is only visible when the reverse-geocoding feature flag is enabled. See Feature Flags for details.
Controls which waypoints are processed:
| Option | Behaviour |
|---|---|
| Only this waypoint | Processes the single waypoint that was right-clicked. Available only when opened via the context menu. |
| Only waypoints with missing location data | Skips waypoints that already have all three fields filled in. Recommended for bulk runs. |
| Update all waypoints | Overwrites existing values for every waypoint in the database. |
Controls how the lookup behaves:
Use corrected coordinates when available — when checked (the default), waypoints with a corrected final location are looked up using those coordinates instead of the original listing coordinates. This is the correct behaviour for mystery and multi-caches where the final location differs from the published coordinates.
Also use online lookup for higher accuracy — when checked, an online refinement pass runs after the offline lookup. The initial state of this checkbox is controlled by Settings → Advanced → Location refinement; you can always override it per-run.
The offline lookup always runs first. Location data comes from GeoNames, a curated global geographic database bundled with the app. It resolves any number of coordinates instantly — no network connection required, no rate limits.
Known limitations:
- The lookup is point-based (nearest known locality), not polygon-based. Waypoints on or very close to an administrative boundary may resolve to the wrong side.
- GeoNames data is periodically updated but may not reflect very recent political changes (e.g. county redefinitions).
- Virginia (USA) has independent cities that are legally separate from the surrounding county. The offline lookup may assign the surrounding county instead of the correct independent city.
When Also use online lookup for higher accuracy is checked, an additional pass runs after the offline lookup using the Nominatim reverse geocoding API (OpenStreetMap polygon data). This provides higher-accuracy results — especially for county — because it uses actual administrative boundary polygons rather than nearest-point matching.
Important notes:
- Requires an internet connection.
- Rate-limited to 1 request per second per Nominatim's usage policy. For large databases this can take a long time (e.g. ~3 hours for 10 000 waypoints).
- Offline results are always written first. The online pass only overwrites a field if it returns a non-empty value — offline data is never erased by a failed or empty response.
- Progress and estimated time remaining are shown in the dialog. You can cancel at any time and keep whatever has been refined so far.
The online checkbox is unchecked by default. To have it checked by default for every run, go to Settings → Advanced → Location refinement and tick Enable online lookup for higher accuracy.
When importing a GPX or PQ zip file, OpenSAK automatically runs the offline lookup for any waypoints that are missing location data immediately after a successful import — no extra step needed.
The online refinement is never triggered automatically on import. To run it, open the dialog manually via Waypoint → Update Waypoint Locations… after the import.