Proposal - Ratify OSM Bunker/ Pillbox nodes, using external data sources
Posted by chris_debian on 29 December 2025 in English.I am proposing a major initiative to “ratify” and enhance the military fortification data on OpenStreetMap. This project actually began with a very specific personal goal: identifying and submitting newly discovered nodes for the UKBOTA (UK Bunkers On The Air) scheme.
UKBOTA is a fantastic amateur radio award program that encourages the “activation” of historical bunkers and pillboxes. While searching for sites to submit to their database, I realized that while many valid sites exist in specialized archaeological records, our coverage on OSM is often incomplete, misplaced, or lacks the specific metadata (like precise coordinates and typology) required for schemes like UKBOTA. This led me to a broader vision: cross-referencing our map with high-quality datasets—specifically the Extended Defence of Britain (eDoB) database.
The Vision
I have been in discussion with Matt Aldred, the lead developer of the eDoB Online viewer, about bridging his extensive research with our global map. The eDoB database is an evolution of the original Defence of Britain project, offering corrected coordinates, Lidar verification, and specific structural classifications.
By aligning these datasets, we don’t just help the radio community; we create a professional-grade, ratified record of these historical assets for everyone. With tens of thousands of potential nodes to process, doing this entirely by hand would be a nightmare. Therefore, I am proposing a structured bulk import and data enrichment project, conducted in full compliance with the OSM Import Guidelines.
Integration with Wikidata
A key part of this project involves strengthening the link between OpenStreetMap and Wikidata. Many significant fortifications already have entries in Wikidata, but the “connective tissue” between the two is often missing.
* I intend to add https://wiki.openstreetmap.org/wiki/Key:wikidata tags to OSM nodes where a corresponding entry exists.
* Where appropriate, I will look into creating or updating Wikidata items with eDoB references to ensure the semantic web of historical data is as robust as possible.
The Methodology: Import & Verification
I intend to seek formal approval from the OSM community for a bulk data merge. However, a “blind” import is not the goal; the objective is to maintain human oversight using modern mapping tools:
- Bulk Import (with Approval): I plan to draft an import proposal on the OSM Wiki to merge eDoB data into OSM. This would focus on adding missing structures and “ratifying” existing ones by aligning coordinates with Lidar-verified data.
- MapRoulette: To handle the scale of this project, I will create challenges to allow the community to quickly review “matches” between eDoB and OSM nodes, ensuring we don’t create duplicates and that Lidar data matches the aerial imagery.
- StreetComplete: For on-the-ground verification, I want to explore using StreetComplete-style quests. This would allow local surveyors to confirm if a pillbox is “extant” (still standing), which is a vital piece of information that external databases can’t always guarantee.
Proposed Tagging Schema
I am proposing a specific tagging schema based on established OSM military tagging:
| Key | Value (Example) | Description |
|---|---|---|
military |
bunker |
Primary classification. |
bunker_type |
pillbox |
Specific subtype. |
pillbox_type |
FW3/24 |
The specific British War Office design type. |
ref:edob |
12345 |
A unique reference ID linking back to the eDoB database. |
wikidata |
Q1234567 |
Link to the persistent Wikidata item. |
source |
eDoB;Lidar |
Acknowledging the data origin. |
Next Steps & UKBOTA Collaboration
My ultimate goal is a “virtuous circle” of data: 1. Import/Ratify: Bring high-quality eDoB data into OSM. 2. Verify: Use MapRoulette and StreetComplete to confirm the sites are still there. 3. Contribute Back: Use this ratified OSM data to identify “new” sites that meet the criteria for the UKBOTA database, providing the amateur radio community with a steady stream of new activation targets.
Next Actions:
-
Community Consultation: I will soon reach out to the UK OSM community and the tagging mailing list to discuss the
ref:edobtag and import logic. -
Licensing Review: Ensuring the eDoB data is fully ODbL-compatible is my top priority.
-
Wiki Proposal: I will be setting up a formal project page on the OSM Wiki to document the process.
-
UKBOTA Outreach: Working with the UKBOTA team to see how verified OSM data can best be formatted for their system updates.
By combining the power of bulk data with the precision of community tools, we can make OpenStreetMap the definitive resource for 20th-century defensive history. I’d love to hear from anyone who has experience with large-scale “ratification” projects or an interest in UK coastal defences.
Discussion
Comment from SimonPoole on 30 December 2025 at 07:27
Shouldn’t this be discussed in the UK forum https://community.openstreetmap.org/c/communities/uk/86 ?
Comment from BCNorwich on 30 December 2025 at 07:58
The last bunker I added isn’t on the KMZ list yet. It S of Holme Hale, Norfolk.
Comment from SomeoneElse on 4 January 2026 at 12:43
Yes, this should be discussed in the UK forum.
With any import like this, conflation is the key. Where there are discrepancies either side here could be correct, and given that this can be fairly hidden, a survey will often be needed to resolve.
I’d also suggest that your proposed tagging seems to miss one very important thing - whether a bunker is in active use by the military or not! An overpass search here finds a bunch that surely are active and a bunch that surely are not. Not all the inactive ones are tagged as such, and where they are OSMers have used a wide range of tagging. I’d instead suggest perhaps
https://wiki.openstreetmap.org/wiki/Tag:disused:military=bunkerfor ones no longer used by the military (althoughhistoricis also used), withhttps://wiki.openstreetmap.org/wiki/Tag:building=bunkerused to describe the extant building, which might be something else now.Comment from Pieter Vander Vennet on 4 January 2026 at 18:02
Oh, it would be interesting to have a MapComplete theme about bunkers, but I don’t have the time to create it. But you can give it a shot at https://mapcomplete.org/studio.html