Today i made my first steps using Claude (sonnet-5) to add coverage, unit and mutation testing to addressextract. The testing needed synthetic input data which claude proudly produced.

I find it really fascinating how it derived the corner cases from the code and made the transformation into an osm.xml which contains all those cornercases.

The first shows admin and postal code boundaries, buildings and addresses in all sorts of relations. Some positions are to evade caching tricks in the Quad Tree. Some really present errors addressextract shall find like address A on node within building outline with address B. All kinds of missing tags, wrong tags, overlapping tags.

Some are to trick the position inside the bounding box, but outside of the geometry.

Fascinating times.

Surprised myself and participated for rrrreal! (well, ok, missed the first day)

Very nice event, liked it a lot.

Report 🫡

https://m-d.me/notes/osm-dailychallenge-2026/

31DayOSMChallenge #Maptober #Maptober2026

Bar Ehiala’S Deck, parte das antenas

On 29 October I presented OSM for Cities at State of the Map Latam in Ciudad de México. The project shows how well OpenStreetMap covers a kind of data in a given city, and how recently anyone touched it.

The slides are online, in Spanish.

Photo by Jordan Jasuta Fischer

Most of the talk was a live demo with Mexico City bus stops, coloured by when each one was last edited. When I made the slides, 317 stops had been edited in the past week, almost all along a few routes in the west of the city. Someone was mapping them right then. Most of the rest had not been touched in over 90 days.

That is what the platform is for, following a dataset over time instead of looking at it once. Save a dataset and it is refreshed from OSM every day, and a notification arrive by email if it changes. A city team can see when its bus stops get mapped, and a mapper can see whether anyone else is keeping their area up to date.

Vector tiles are coming soon

Today a dataset loads into the page as one GeoJSON file. That works for bus stops, but not for the buildings or streets of a large city, which is why those are not on the platform yet.

Buildings matter most for disaster response and health planning. They show where people live, which is what a house-to-house campaign during an epidemic needs.

The fix is to bake each dataset into vector tiles (PMTiles), so the browser only loads what is on screen. It is ready and in testing, and should be released soon.

Thanks, State of the Map Latam!

It was great to be in Mexico City and see old and new friends from the OpenStreetMap community. The conference was very well organized, with an amazing diversity of talks. I’m looking forward to the next one, which will be both Latin American and global, State of the Map 2027, in Bogotá, Colombia.

Disclaimer: Written by me with AI assistance.

Registered in 2014, but I only started using OpenStreetMap actively last year.

After watching some Aboriginal movies of Australia, I switched from the Himalayas to Down Under, and then with chasing tracks in the outback of Australia—uncovering hidden reservoirs, basins, homesteads, cattle stations, farms, and surprisingly, some generous peaks. From there, I switched over to China, where the clever use of land through greenhouse horticulture stands out as one of the best examples of resourcefulness.

Flipping to Ethiopia brings a blend back to Nature: homes and huts constructed from natural elements offer a grounding perspective, even as the region slowly turns toward the so-called “blinded modernization.” Crossing over to South America, dense forest covers reveal hidden streams and alpine lakes tucked high in the mountain ranges, though the sheer scale of deforestation is disheartening to see.

Jumping to Japan and the Korean peninsula, the structured, disciplined approach to farming is among the finest in the world, matched by remarkable urban and human development.

Further north, the vast expanses of Alaska and Siberia ground you completely—reminding us of our fragile place within Nature and how quickly our so-called "development" will simply be reclaimed by time.

OSM has helped keep me calm, though it is still easy to get agitated. Now, I’ve even started mapping via my mobile browser as well, which has been a lifesaver while traveling on public transport. In a world full of towering billboards and aggressive roadside slogans, mapping on the move gives me the perfect excuse to ignore the visual pollution.

Of course, whenever I'm passing through true valleys and breathtaking landscapes, the phone goes straight into my backpack so I can take it all in.

Title: OpenHVRA: a free hazard, vulnerability and risk assessment tool built on OpenStreetMap

Hello mappers!

For years I have watched the same thing happen. A flood or any hazard hits a place, and the first questions are always the same: how many people live near the river, which schools and health posts are in the way, and what will it cost? Very often the best data to answer those questions is already sitting in OpenStreetMap, mapped by volunteers. But turning those buildings and waterways into a risk picture usually needs desktop GIS, paid software, or a specialist.

So I built a tool based on my professional experience, OpenHVRA (Open Hazard, Vulnerability and Risk Assessment) with help of my friend Claude, a free web map that does that analysis straight in the browser, using only open data.

Try it: gomalhunzai.github.io/openhvra Code (MIT License): github.com/gomalhunzai/openhvra

No login, no install.

How it works

You draw an area on the map (or upload a boundary as Shapefile, GeoJSON, KML, GeoPackage and a few other formats). OpenHVRA pulls buildings, roads, waterways and facilities from OSM through the Overpass API, adds open elevation tiles, and walks you through eight steps:

1. Area and data: download OSM layers, with a “light” mode for slow connections.
2. Population model: estimates residents per building from footprint and storeys, which you can calibrate with a census total.
3. Cursor probe: hover anywhere and see live counts of people, buildings and facilities within a radius.
4. Exposure by distance: what lies within X metres of rivers, streams or roads. It also checks height above the channel, so homes high on a hillside in a mountain valley are not wrongly counted as flood-exposed.
5. Flood risk and risk finance: flood depth per building for different return periods, damage using JRC depth-damage curves, average annual loss, and how losses could be split between reserves, credit and insurance.
6. Social vulnerability: a 0 to 1 index per home based on access to health care, emergency services and roads, housing fragility and crowding, plus optional census data and World Bank figures for vulnerable groups.
7. Multi-hazard risk: scores every building for river flood, flash flood, landslide, earthquake (USGS catalogue), coastal flood, glacial lake outburst flood (GLOF) and snow avalanche, then combines hazard and vulnerability into one risk score and a likelihood × impact risk matrix.
8. Report and downloads: one click gives a ZIP with CSVs, GeoJSON layers, 300 DPI map layouts and charts, all stamped with the tool version so results can be traced and cited.

There is also a 3D view that raises buildings to their mapped height over the terrain, which turned out to be a great way to explain risk to people who do not read maps every day.

Where you come in: better mapping, better risk estimates

OpenHVRA is only as good as the map underneath it. Some tags make a real difference:

• building:levels drives the population estimate and the 3D view. Even a rough count of storeys helps a lot.
• Building type (building=house, hut, apartments, commercial, etc.) feeds both the population split and the housing fragility score. Plain building=yes gives the tool much less to work with.
• Waterways drawn in the direction of flow are used to trace GLOF paths. A stream drawn backwards breaks the trace.
• Health facilities, schools, shelters and emergency services (amenity, healthcare, emergency) are what the critical facility analysis counts. If the clinic is not on the map, it is not in the report.
• Bridges and road classification matter for access and exposure.

If you run mapathons for disaster preparedness, this is a nice way to show volunteers what their mapping is used for: map an area, then open it in OpenHVRA and see the risk picture appear.

Status and feedback

OpenHVRA is in beta (v0.10.1). The methods are documented in the README and CHANGELOG, and version 1.0 will come once they are validated against real events. It is a screening tool to help prioritise, not a replacement for a detailed engineering study.

I would really like to hear from you:

• Try it on an area you know well and tell me if the numbers make sense.
• Open an issue on GitHub for bugs or ideas.
• If you use it in a project, mapathon or paper, please let me know. The “Cite this repository” button on GitHub gives you a citation.

Thanks to everyone who keeps mapping the places that need it most. This tool exists because of you.

Happy mapping!

Za poslední půlrok proběhlo výrazné oživení několika menších měst v Jižních Čechách. Namátkou jmenuji Jindřichův Hradec, Prachatice, Vimperk, Třeboň… tedy města, kde místní OSM mapovači asi jen tak nežijí.

Nemluvím jen o prostém doplnění zákresu podle letecké mapy, která je každým rokem detailnější, ale i zpřesnění různých cest v okolí, objektů a subjektů, typicky firem a obchodů v městě. To je výsledkem práce více lidí, nevím přesně, ale věřím že mnoha. Za mne jsem dostával i tipy přímo od lidí z místa, například z místního obecního, nebo městského úřadu.

A nutno říct, že oni mají občas velmi konkrétní informace, které se u jiných veřejných zdrojů nedají vidět. Jen je trochu nelehké to info posbírat. Chvilku mi trvá, než si na každé mapované místo zvyknu, stane se mi víc známým. Vidím v něm něco prostorově unikátního. Z fotografií se dozvím, že město má nějakou tvář, nějaký profil… tvar vycházející nejen z historie, ale i z krajinných dispozic. Když vidím že náměstí je celé z kopce, hned to na mne působí jinak.

Ještě je hodně jiných měst a obcí, zajímavých oblastí, kde jsou úpravy třeba 10 a více let staré. Současnost je už jiná. Nejen v popisu míst, ale i v rozvoji periferií, v přirozeném městském prostředí kde jsou kulturní i komerční body zájmu.

Do pozornosti přijdou města jako např. Blatná, Milevsko, Domažlice… Zajímavé k mapování pro mne byly i některé oblasti Šumavy, Novohradských hor, dalších mikroregionů. A nemusí být jen turisticky atraktivní.

Přijde mi to jako sbližování s místy, kde jsem ještě nebyl. Až se tam někdy vydám, už budu vědět líp, kde právě jsem.

Budu mít totiž s sebou mapu!

Motion extraction tutorial: https://youtu.be/NSS6yAMZF78?t=226

This mapping was a while ago. This is also a diary entry repost, I figured out how to display GIF-files. I was using imgur before this, where all GIFs you upload are converted to mp4 automatically so I can’t display it in the diary. Imgur is also full of ads. I assume most people don’t use adblockers, even with adblockers the UI distracts from your file. I’ll go back through my imgur links on OSM and reddit and link them instead to images on my little github page.

OSM LATAM 2026 México 🇲🇽 — Day 3: Beyond the Map!

And just like that, we reached the final day of OSM LATAM 2026 México! 🚀

What an incredible journey these three days have been. Day 3 brought another packed schedule of inspiring talks, practical experiences, new ideas, and, above all, more opportunities to connect with the amazing people behind OpenStreetMap.

🔗 Event website: https://www.osmlatam.org/sotm/2026-en/

📅 Full schedule: https://pretalx.cienciaenmexico.com/sotmlatam2026/schedule/

🌎 Learning from the global community

The day featured keynote talks from the Humanitarian OpenStreetMap Team (HOT) and OpenStreetMap US (OSM-US), alongside a rich program of presentations and discussions.

Throughout the day, we enjoyed a wide variety of talks covering practically everything OSM: mapping, routing, tagging, data quality, community engagement, and much more.

We also learned about MapRoulette challenges for local governments, an interesting way to encourage collaborative mapping and help improve geographic data in areas of particular interest.

❤️ Mapping with and for communities

Perhaps the most meaningful part of the day was hearing about projects that put communities at the center of mapping.

Teams shared their experiences working with vulnerable communities across Latin America, showing how OpenStreetMap can help local governments make informed decisions and prioritize actions where they are needed most.

Another inspiring project introduced elementary school children to mapping through playful activities, using playdough and stickers on top of OSM maps.

Particularly remarkable, these initiatives reached remote communities, some hours away by car from the nearest place with telecommunications access!

These experiences highlight something truly important: OpenStreetMap is not just about collecting geographic data; whether working with local governments, vulnerable populations, or children discovering mapping for the first time, its impact goes far beyond the map itself.

🧭 Taking mapping into the streets!

We also had an exciting hands-on mapping activity using Sketch Map Tool and ChatMap, adding even more tools to our mapping toolkit!

We headed out to the streets surrounding the main event venue, combining paper-based mapping with photography and on-the-ground observations.

It was a great opportunity to explore different ways of collecting local knowledge, documenting our surroundings, and bringing real-world observations into OpenStreetMap.

Sometimes the best way to understand a place is simply to walk through it, observe, ask questions, and listen to the people who know it best.

🌱 Beyond the Map

Throughout these three days, one thought kept becoming clearer to me:

The real treasure of OpenStreetMap is its communities. They are its backbone, its driving force, and its greatest strength.

We have amazing technologies, innovative tools, sophisticated data processing, routing engines, imagery platforms, and countless ways to improve the map.

But none of it would mean nearly as much without the people behind it.

People who volunteer their time, share their knowledge, organize mapping activities, teach others, build tools, collaborate with institutions, and work alongside communities that need better geographic information.

The map is the result, but the community is what makes it possible.

And perhaps that is what Beyond the Map really means: recognizing that our contributions can create value that extends far beyond geographic data, helping people become more connected, informed, represented, and empowered.

🚀 The Journey Continues!

There was certainly a little sadness when the event finally came to an end. It is always difficult to say goodbye after sharing such an enriching experience with so many wonderful people.

But I’m sure everyone is taking something valuable home. I know I am — I learned a ton!

Some of us discovered new tools, others gained new perspectives, many made new friends, and perhaps some even started building partnerships that will lead to future projects and collaborations.

Another heartfelt THANK YOU to all the organizers, sponsors, allies, speakers, volunteers, local governments, venue staff, and every attendee who contributed to making OSM LATAM 2026 México such a memorable experience.

Three days of learning, sharing, mapping, and connecting — but the work and the adventure continue!

Beyond the Map. Beyond the Data. Together, we make a difference. 🗺️❤️

 #OpenStreetMap #OSMLATAM #OSMLATAM2026 #HOT #OSM-US #OpenData #MappingTogether #BeyondTheMap

Apps baru mapku mengunakan map ini terima kasih semua kerana berkongsi

OSM LATAM 2026 México 🇲🇽 — Day 2: Transmute the Map!

Day 2 of OSM LATAM 2026 México brought us another incredible day of learning, collaboration, and community!

🔗 Event website: https://www.osmlatam.org/sotm/2026-en/

📅 Full schedule: https://pretalx.cienciaenmexico.com/sotmlatam2026/schedule/

As every great adventure, the day had its ups and downs. We ended up with two breaks instead of one, but what could have been a downside turned into another opportunity to meet fellow mappers, exchange ideas, and strengthen the connections that make our community so special.

🌎 Collaboration over competition

One of the highlights was hearing keynote talks from sponsors HERE and Overture Maps, learning more about who they are, how they work, and how they collaborate with OpenStreetMap to improve geospatial data.

Sometimes, companies working in the mapping world can be perceived as rivals to OSM. But today’s conversations remind us that the geospatial ecosystem is much bigger than any single project or organization. There are meaningful ways to collaborate, share knowledge, and support open data. Different approaches can complement one another, and the entire community can benefit.

We also had a special talk from Daniela Waltersdorfer, an OpenStreetMap Foundation (OSMF) Board Director, about the Foundation’s role in the OSM ecosystem.

A particularly important takeaway was that the OSMF’s mission is to support OpenStreetMap, not control it. The Foundation helps keep our community healthy and growing while providing the organizational and technological backbone needed to sustain the project for the long term. The map belongs to its community, and that distinction matters!

🗺️ Mapping that makes a difference

Throughout the day, we enjoyed amazing talks exploring how mapping helps local communities, how public transport mapping can improve mobility, and why open geospatial data matters.

We also heard about the production, processing, and analysis of data, between OpenStreetMap and local governments. These exchanges are particularly valuable because they help bridge the gap between community-driven mapping and public institutions, opening opportunities to put geographic information to practical use.

Every road mapped, every bus stop and public transport station added, every building documented, and every dataset made accessible can help someone understand their surroundings and make better decisions.

And this brings us to a thought that stayed with me throughout the day:

What if mapping is a way of transmuting the map — and, in turn, allowing the map to transmute communities into better versions of themselves?

We transform observations into data, data into knowledge, and knowledge into opportunities for action. As the map becomes more complete and useful, it can help communities become more connected, informed, accessible, and resilient.

Transmute the map. Transform the community. ❤️

🤝 A milestone for the Colombian OSM community!

Another wonderful piece of news was the official signing of the Local Chapter Agreement between the OpenStreetMap Foundation and the Asociación de Cartografía Colaborativa de Colombia (AC3).

Following its acceptance in March 2026, this agreement formally recognizes AC3 as an official Local Chapter of the OSM Foundation.

A huge congratulations to AC3 and the entire Colombian OpenStreetMap community, and a big thank-you to the OSMF for continuing to support the growth and organization of our global community!

Local Chapters help strengthen the connections between the global project and the people building it on the ground. This is a fantastic milestone for Colombia and an inspiring example for the wider Latin American OSM community. 🇨🇴🎉

🔥 SotM Latam 2027 is starting to take shape!

During the General Assembly of the OSM Latam Community, we started looking ahead to the next chapter of our regional gathering.

The next State of the Map Latam is already beginning to take shape! SotM Latam 2027 is cooking! 🔥

There is something exciting about knowing that while we celebrate what our community has accomplished today, people are already working to create the next opportunity for us to meet, learn, and build together.

🏛️ Closing the day with history and culture

To wrap up the day, we enjoyed a guided cultural walking tour around Templo Mayor, right in the heart of historic downtown Mexico City.

After a full day discussing maps, technology, communities, and the future of open geospatial data, it was a wonderful way to reconnect with the history and culture of the place hosting us. The city itself became another layer of the experience — a reminder that every map represents places filled with history, identity, and human stories.

A huge thank-you to everyone who made Day 2 so enriching: the speakers, sponsors, organizers, volunteers, fellow mappers, and everyone who shared their knowledge and enthusiasm.

We are not just creating a map. We are building connections, empowering communities, and opening doors to new possibilities.

Transmute the map. Transform the world. 🗺️❤️

Looking forward to another day of learning, mapping, and growing together at OSM LATAM 2026 México!

 #OpenStreetMap #OSMLATAM #OSMLATAM2026 #OpenData #MappingTogether #TransmuteTheMap

1) In Vespucci, create a custom layer named “Strava-cookies” with the following URL: https://content-a.strava.com/identified/globalheat/all/hot/{z}/{x}/{y}.png?px=256.

2) Next, you need to retrieve cookies from the Strava website. To do this, install the JOSM Strava Heatmap browser extension on a PC. Use this extension to obtain the cookies.

3) Create an XML file with the following content:

<?xml version='1.0' encoding='UTF-8' ?>
<Configuration>
    <Section name="tilelayers" table="headers" 
version="0.1" truncate="false">
        <ColumnTypes id="TEXT" name="TEXT" 
value="TEXT" />
        <PrimaryKeyColumns />
        <Row id="Stravacookies" name="Cookie" 
value="***"/>
    </Section>
</Configuration>

Replace *** with the cookies you retrieved.

4) In Vespucci, go to “Tools” and select “Import configuration.” Locate the file you created.

5) Enable the “Strava-cookies” layer.

Alternative method (without using a PC): Open the link mentioned in step 2 using the Firefox mobile browser. Follow the link provided there for Firefox. Enable “Desktop site” mode in the browser, install the extension, and then proceed as described above.

Cookie values change every few days; therefore, if the layer stops working, you will need to update the XML file and re-import it.

After 3 years i continue the series of OSM antipatterns. This time - Indecisive topology.

For example it means that a ditch is either on the left or right of the footway. It does not cross it by accident. So typically it stays on one side, and then crossed at nearly a 90° angle. It wont cross in a 5° angle

Here is a different example. Somebody could not decide whether the footway belonged to the industrial area or not. It meanders around between inside and outside.

This antipattern is not per se wrong - but its indecisive. It makes hard to decide if the footway is a private footway in an industrial area, or if its public. You cant tell from looking at the map.

Objects should either be within, or around some other object, or clearly have a state transition at a border. They rarely overlap just randomly.

Given my last post in the Antipattern series concerning Indecisive topology i generated a debug map. Currently there is one for Germany and Austria.

It shows ways crossing in an angle between 1-15°. I currently exclude boundaries, pipelines, powerlines and tunnel alike objects.

The short of the two segments is being flagged here.

All these issues may not be real errors. But when mappers use the Antipattern of Indicesisive topology there is typically something broken and needs your Love.

You can create your own excerpts - A mirror of the code can be found here github.com/flohoff/linecrossing

It can either dump the results in a GeoJSON or an sqlite. For my debug map i use the sqlite export.

OSM LATAM 2026 México 🇲🇽 — Day 1: Connecting, Learning, and Mapping Together!

I had the wonderful opportunity to attend OSM LATAM 2026 México, and what an amazing first day it was!

It was a pleasure to meet so many incredible mappers, connect with fellow community members, and share knowledge, experiences, and ideas around OpenStreetMap. I also enjoyed participating in community talks and learning about the new technologies and tools being developed to further support OSM and its community.

One of my personal highlights of the day was discovering Maprizon, a state-of-the-art street-level imagery platform from Kaart, and fAIr, a collection of AI-assisted mapping tools from HOT. It was exciting to learn about these developments and explore how emerging technologies can help us improve our mapping workflows and contribute even more effectively to OpenStreetMap.

Events like this remind us that OpenStreetMap is much more than a map. It is a global project powered by people, collaboration, shared knowledge, and a common passion for open geographic data.

A heartfelt thank you to all the sponsors, allies, organizing committees, speakers, volunteers, local governments, venue staff, and all the amazing people attending and making this event possible.

It has been an inspiring first day, and we’re already looking forward to continuing tomorrow, learning more, exchanging ideas, and honing our mapping skills together!

OSM LATAM 2026 México! 🗺️❤️

 #OpenStreetMap #OSMLATAM #OSMLATAM2026 #Maprizon #fAIr #MappingTogether

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Schulungen zu OpenStreetMap: ab Januar 2027

Die Frage kommt oft: Könnt ihr uns zeigen, wie OpenStreetMap funktioniert? Bisher fehlte uns die Kapazität. Doch das wird sich bald ändern, denn unsere Koordinierungsstelle hat Verstärkung bekommen.

Im Februar 2026 hat die Deutsche Stiftung für Engagement und Ehrenamt (DSEE) unseren Antrag auf Förderung bewilligt. Das gibt uns Gelegenheit ein Schulungsangebot zu OpenStreetMap aufzubauen.

Bis Ende 2027 Schulungen aufbauen

Insgesamt stehen dem Projekt rund 100.000 Euro zur Verfügung. Es ist eine Anschubfinanzierung: Danach soll sich das Angebot aus dem laufenden Betrieb tragen. Mit den Mitteln finanzieren wir zwei Personen, eine für die Inhalte, eine für das Organisatorische.

Es wird daran gearbeitet

Im April konnten wir Mathias Gröbe gewinnen. Er entwickelt die Inhalte. Er ist promovierter Kartograph, seit 2012 bei OpenStreetMap und gibt Workshops und Lehrveranstaltungen. Er moderiert die AG OSM-Schulungen, in der Community-Mitglieder die Inhalte mitgestalten.

Seit Oktober ist Fränze Kellig an Bord. Sie hat in Berlin eine Kulturgenossenschaft geleitet und Kommunikation für Unternehmen entwickelt. Fördermittelverwaltung kennt sie aus der Praxis. Bei uns organisiert sie die Schulungen: Gespräche mit Interessierten, Anmeldungen, Termine und Budget. Dazu macht sie das Angebot bekannt und unterstützt Katja Haferkorn bei der Koordinierungsstelle.

Was ist schon geschafft

• Die ersten Schulungsunterlagen sind erstellt.
• Aktuell entwickeln wir Folien, insbesondere für Naturschutz und Feuerwehr.
• Die Webseite ist in Vorbereitung.
• Ab Januar laufen die ersten Pilotschulungen. Wir probieren die Module mit ersten Gruppen aus und bessern nach.

Für wen das ist

Die Schulungen richten sich vor allem an gemeinnützige Vereine. Sie lernen, wie sie die Daten nutzen können, und werden Teil der Community.

Ansprechpersonen:

• Mathias Gröbe: mathias.groebe@fossgis.de
• Fränze Kellig: fraenze.kellig@fossgis.de