Hello, my name is Sean Gillies, and this is my blog. I write about running, cooking and eating, gardening, travel, family, programming, Python, API design, geography, geographic data formats and protocols, open source, and internet standards. Mostly running and local geography. Fort Collins, Colorado, is my home. I work at TileDB, which sells a multimodal data platform for genomics and precision medicine. I appreciate emailed comments on my posts. You can find my address in the "about" page linked at the top of this page. Happy New Year!

Snow-covered cones, craters, and lava flows of Craters of the Moon National Monument in Idaho, viewed from an airliner traveling between Denver and Seattle on February 21, 2025.

Chers Partenaires et utilisateurs de la plateforme territoriale Guyane-SIG,

L'équipe de Guyane-SIG vous adresse ses meilleurs vœux pour l'année 2026 !

Après une année 2025 riche en rencontres et en animations (webinaires thématiques, assemblée générale, salon des maires, formations, séminaire), l’année 2026 s’inscrit dans la continuité, toujours avec l’objectif de catalyser la coopération régionale en matière de production, de partage et de valorisation des données géographiques en Guyane. Des améliorations significatives ont une nouvelle fois permis de faire progresser l’ergonomie des outils, d’améliorer l’accessibilité de nos ressources et de poursuivre le programme d’animation.

Nous avons hâte de vous retrouver au cours des nombreuses animations à venir au cours de cette année. 

La rencontre mensuelle des contributeurs habitants Montrouge et alentours aura lieu le jeudi 05 février 2026 au  Schmilblick à partir de 19h.

Ce bar solidaire est situé au 94 avenue Henri Ginoux (station Vélib juste en face, bus 68 et 128, métro 4 station « Mairie de Montrouge »).

Cette rencontre mensuelle nous permettra de discuter de nos projets de cartographie dans OpenStreetMap à Montrouge, au Sud de Paris et au-delà. Comme d’habitude, nous prenons un pot et dînons sur place pour ceux qui le souhaitent.

Comme toujours, les débutants et simples curieux sont les bienvenus.

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[1] Participants à ce qui est sûrement le premier mapathon de 2026 à Braga, Portugal | © waldyrious

« The Refugee Project » est une expérience pédagogique créée pour sensibiliser le public au sort de millions de personnes à travers le monde, qui n’ont eu d’autre choix que de fuir leur foyer. Le projet a été créé par Hyperakt et Ekene Ijeoma, qui remercient le HCR pour l'accès à plus de 50 ans de données sur les migrations de réfugiés, à ses archives numériques complètes de témoignages de réfugiés publiés et à des photographies originales.

Le nombre de réfugiés par pays d'origine et pays d'asile (therefugeeproject.org)

Melinda Clarke, the creator of the Melbourne Map has branched out with a range of beautiful silk scarves with some very stylish map designs including, of course, The Melbourne Map. n this pic my pal Denise McKenzie is wearing Melbourne at the GeoBusiness conference.

Here’s Melinda with her vintage New York scarf

And here she is with the Melbourne map

You can order the scarves from her site at https://www.themelbournemap.com.au/collections/scarves, a beautiful gift for a map lover.

Finally it’s here: Jupyter notebooks inside QGIS. I don’t know about you but I’ve been hoping for someone to get around to doing this for quite a while.

Qiusheng Wu published the first version of the Notebook plugin on 26 Dec 2025. Late Christmas present?!

For the setup, there’s a handy tutorial by Hans van der Kwast and, additionally, Qiusheng published an intro video:

Development is going fast (version 0.3.0 at the time of writing) so there will be new features when you install / update the plugin compared to both the tutorial and the video.

Click on image above to view the map

Do the levels of deaths from mass shootings in the US correlate with the gun policies of individual states? I thought this might be an interesting topic to explore in my journey of mapping with AI, you can draw a conclusion from the screenshot above or wait until you get to the end of this post for my thoughts. Mapping wise – I also wanted to explore building a fairly complex map with a detailed prompt to see how close I could get in one go.

This is not the opening screen of some Esri software, it’s the in-flight mapping system on Ken’s last flight to the UK

Au XIXe siècle Pierre de Coubertin, aristocrate pacifiste libéral, a voulu contribuer à la paix des nations par la compétition sportive et a théorisé la « neutralité du sport » à travers l’olympisme. Comment le CIO (Comité international olympique) a-t-il pris le contrôle du sport international ? Comment le sport est-il devenu le lieu de la projection des puissances et un outil stratégique diplomatique de la géopolitique ?

Pour traiter ce vaste sujet, Patrick Clastres, historien du sport et des jeux olympiques*, Professeur à l’Université de Lausanne (ISSUL/CRHIM), directeur du Centre d’études olympiques et de la globalisation du sport, s’entretient pour ce dernier café de l’année 2025 au Café de Flore avec Micheline Huvet-Martinet.

P. Clastres (à droite) et M. Huvet-Martinet (photo M Vignaux)

I started out trying to make web maps with WebMapperGPT and then Google Gemini to scratch an itch after my pal Ken Field said he was going to make a map a day in 2026. I thought I would give it a try and as some of the previous posts in this thread have shown I have been able to make some reasonable web maps with quite nice design and interaction (IMHO). But it isn’t easy and it’s certainly not a miracle coding solution.

My coding expertise is non existent – I do not know anything about JavaScript, I can edit but not create html pages and CSS with guidance and I have used mark-down a few times. My cartographic skills are quite limited and are a combination of self taught (not good) and correction by ridicule (Ken Field), I can use QGIS but am only a basic level user. Bottom line I couldn’t build one of the maps that I have built without assistance from AI.

Nyall Dawson has been working on FOSS4G projects since 2013, having contributed to numerous projects such as QGIS, GDAL, and PROJ. He is best known as a key, longstanding core contributor to QGIS, with over 24000 commits (and growing).  Nyall …...

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We are honoured to announce that Nyall[1] is the recipient of the 2025
Sol Katz Award (the 21st year of the award) at the recent FOSS4G event
in Auckland, New Zealand.

Nyall Dawson has been working on FOSS4G projects since 2013, having
contributed to numerous projects such as QGIS, GDAL, and PROJ.

Marc Tobias spotted this old school map in Ed Frefogles home. It’s pretty nig!

En entornos donde cada segundo cuenta, la capacidad de gestionar, visualizar y analizar información geográfica de forma precisa es un factor determinante para el éxito operativo. Desde la Suite gvSIG, estamos impulsando una solución integral diseñada para modernizar las Infraestructuras de Datos Espaciales (IDE) y optimizar los procesos de respuesta ante emergencias y asistencia ciudadana.

Nuestra propuesta tecnológica se basa en la integración de tres pilares fundamentales que cubren todo el ciclo de vida del dato espacial:

PgRouting est une extension permettant de réaliser des calculs d’itinéraires et analyses de réseaux dans votre base de donnée géospatiale PostgreSQL.

Elle est développée en C++, à l’aide de la bibliothèque Boost Graph et dépend de l’extension PostGIS. Elle permet d’envisager des analyses de réseaux sous plusieurs angles : analyse de la structure des graphes, calcul d’itinéraires simple ou multiples, analyses d’accessibilité… L’avantage de cette bibliothèque open-source est que tous les calculs sont réalisés en base de données et donc ne nécessitent aucune installation d’outil supplémentaire. Le point commun des fonctions de routage de cette bibliothèque est d’utiliser de façon sous-jacente une notion de graphe.

Discussion entre contributeurs.trices viennois.es du projet OSM et acteurs intéressés.

Toute personne intéressée par OpenStreetMap peut s'intégrer à cette rencontre, tout particulièrement les débutant.e.s qui souhaiteraient des conseils pour se lancer.

Ordre du jour à compléter: https://wiki.openstreetmap.org/wiki/FR:Vienne_(Is%C3%A8re)/Reunion-2026-01-21

Lieu de réunion: Ninkasi, 15, impasse du Rond Point, 69210 Saint-Romain-en-Gal - à partir de 18h30

Un fichier parquet bien construit oriente le requêteur en lui disant d’abord où ne pas aller. Plus il ferme de portes à votre requête SQL, moins elle se perd en explorations inutiles, plus vite elle avance vers l’essentiel.

C’est exactement la logique du data skipping : éviter de lire ce qui ne sert à rien.

Pour cela, le format parquet dispose de trois leviers complémentaires — dont deux sont bien connus, et un troisième, plus discret : les filtres de Bloom.

Premier levier : des colonnes physiquement séparées.
Parquet est un format orienté colonnes. Si une requête ne porte que sur 3 colonnes d’un fichier qui en contient 20, alors les 17 autres ne seront tout simplement jamais lues. 

“World of communication’, in Rome, in the National Gallery of Modern and Contemporary Art. It dates from 1972 and is made by Jiří Kolář. ” I htink the collage on the globe is made with postage stamps.

We are happy to announce that the QGIS User Conference 2026 will take place on 5–6 October 2026 in Laax, in the heart of the Swiss Alps. Visit the conference website to find out all details.

The conference will be hosted at Crap Sogn Gion, at 2,222 metres above sea level, offering a unique setting with panoramic mountain views and direct access to the surrounding alpine landscape. Despite its mountain location, Laax is well connected by public transport and provides a wide range of accommodation options in the valley.

As Chair of the QGIS Project and of the QGIS User Conference 2026, I’m very much looking forward to welcoming the community in my hometown and place of birth of QField.

Le groupe local Nancy de l’association OpenStreetMap France vous propose de participer aux réunions mensuelles ouvertes à tou·te·s !

Avec OpenStreetMap, participez à la construction d’une carte en ligne libre et gratuite, partagée avec le monde entier!

Le lieu la Fabrique des possibles nous est librement accessible lors de nos réunions.

Reinder spotted these mappy suitcases in a hotel window in Rome. He was so taken with them that he didn’t mention the nice looking globe, while his wife apparently was more impressed by the towels folded as swans. Go figure!

If only those cases were a bit bigger and had wheels.

La red GeoLIBERO ha sido reconocida oficialmente como Red Emérita por el Programa CYTED. Este reconocimiento fue aprobado por la Asamblea General celebrada en noviembre de 2025 en Asunción (Paraguay) y supone, sobre todo, un respaldo al trabajo colectivo que venimos desarrollando desde hace años en torno a la geomática libre en Iberoamérica.

Además, he sido nombrado coordinador de la Red Emérita GeoLIBERO para el periodo 2026–2029, una responsabilidad que desde la Asociación gvSIG asumimos con orgullo y con muchas ganas de seguir impulsando esta comunidad.

Throughout the week, in workshops, presentations, and project showcases, a consistent theme emerged: QField is not just “the mobile companion to QGIS,” it is production infrastructure for complete field-to-cloud-to-desktop workflows.

It was incredible to see how present QField was throughout FOSS4G 2025 in Auckland. With around 20 presentations and workshops featuring QField, the conference showcased a wide range of real-world, production-grade use cases across many sectors. 

What stood out was not just the number of talks, but how consistently QField was presented as a trusted, operational tool rather than an experiment.

Reinder spotted this mosaic map of the Old City of Rome, “Saw this in the lobby of the Santa Chiara hotel in Rome. The size of the map is let’s say 50 x 70 cm, it is made of little stones of approximately 4 x 4 mm. No artist is mentioned — but he or she deserves our respect. Ciao!”

Click the image to go the Unequal London Map (v2)

I was quite pleased with the first version of the Unequal London Map, but by the time I had crawled over the finish line I realised that there were several choices that I had made which were less than ideal, particularly with regard to the data I selected. I thought it should be quite easy to build another version with more/different data and remedy some of the other issues. I decided to start with Gemini to avoid the usage limits with WebMapperGPT.

The first stage was to identify the data that I could use to give a better view of inequality in London. I started with this prompt:

Mardi 13 janvier 2026, de 19h à 21h, Café de Flore, salle du premier étage, 172 boulevard Saint-Germain, 75006 Paris

Pour ce café géo sur les zoos, nous accueillons Jean Estebanez, géographe à l’université Paris-Est Créteil. Ce sujet original aborde la question des rapports entre les humains et les animaux.

Les zoos ne sont pas qu’un espace d’exploitation, ni de conservation du futur, mais avant tout des élevages, c’est-à-dire des espaces de vie en commun. La visite des zoos crée une tension entre vie et morts, joie et regrets, sauvage et domestique. Autrement dit, la réflexion sur les zoos met en avant la centralité et l’ambivalence du processus de domestication dans nos liens aux animaux.

Remember Santa’s Delivery Route from Xmas Eve? Ken sent me this modern version of that map which he spotted in the lobby of the Great Northern Hotel next to Kings Cross. Note that this time the map is north up.

After the relative success of my first attempt to build a map with WebMapperGPT (WMGPT) I wanted to try something a bit more ambitious. A conversation about how in most parts of London rich and poor live relatively close to each other, prompted me to try and build a map to illustrate Unequal London.

This was a much more complex project with several stages:

25/12/2025-31/12/2025

[1] « Sisparnas » développé par le Ministère du tourisme de la République d’Indonésie | Leaflet – données cartographiques © contributeurs et contributrices OpenStreetMap.

Last one from Reinder’s Rome trip. “I saw these on the Via dei Fori Imperiali in the Eternal City: quite spectacular!”

I don’t know where to start with this one. Yes it is a map in the wild, but why would anyone make this decaying world held by rotting hands and then award it as a peace prize? I thought FIFA governed world football, is it really FIFA’s role to award peace prizes? As for the recipient, I think the jury is out.

This could have been an April Fool’s post but I thought it might serve as a starter for 2026. Mappy New Year!

Melinda Clarke (of Melbourne Map fame) sent me this, she said

“I met this young girl, we got chatting and I shared that I was producing a map of Melbourne. She then declared her love for maps, and travelling around the world – and showed me her tattoo of a world map on the soles of her feet!  If you look closely – she has even included NZ ! I am thinking a tattoo on the soles of your feet might just have hurt a bit. ” 

What a map in the wild! I think that is “above and beyond”

This has to be one of the best maps in the wild ever!

Elizabeth sent me this from Weymouth “Last night on the South Coast. Looks like the map of UK, Ireland and Denmark.”

Mappy New Year to everyone who contributes maps in the wild or follows us, let it be a year full of whacky maps.

Wandering in Covent Garden I spotted this advert for the Omega Speedmaster watch which has a cute globe panel and a Snoopy graphic. Who knew that Snoopy was the official Mascot for the NASA Space Programme with the agreement of Charles Schulz?

Gaëlle Sutton shared these maps a bit before Christmas. The season is still on. Happy Holidays.

A major accomplishment in 2025 was re-achieving CITE Certification status for GeoServer. Many thanks to all who were involved! After approximately 10 years, we can once again officially confirm that GeoServer is OGC compliant.

Maintaining Certification is an annual expense for the project - and a sponsorship opportunity for you!

Thanks to Gaia3D and OSGeo:UK for sponsorship covering the expense of CITE Certification for 2025.

Our 2025 CITE Certification for GeoServer 2.27 expires on January 9th.

Reinder shared this Christmas card designed by Patrick Bergsma

18/12/2025-24/12/2025

[1] Application web basée sur OSM pour afficher les éléments Wikidata autour d’un lieu | © Rtnf | Données cartographiques © Cartographes OpenStreetMap.

...

An absolute cracker from Wanmei L, shame she didn’t say where she spotted it. Seems like a good one to kick off this years 12 Mapppy Days of Christmas

I wasn’t sure whether to share this but the editorial board said “F it, go for it”

This tattoo is on the arm of Arsen Ostrovsky, a survivor of the Bondi Beach Chanukah shooting – no further comment needed.

Ken spotted this on US TV – I think it would make a great caption contest. Go for it!

Reinder spotted this magnificent illuminated globe at the railway station in Leiden. I think it’s a perfect choice for our Xmas day post.

Happy Christmas to all who celebrate it and Seasons Greetings to the rest of you.

A few days ago, my pal Ken Field posted about a new project he is planning for 2026:

“Ten years ago I had an idea to write about a map a day for a year. I’ve had another idea… Introducing the #365DayMapChallenge where Ian Muehlenhaus and I will make a map a day, using only natural language prompts and AI, for a whole year. More here: https://mapdesign.icaci.org/2025/12/the-365-day-map-challenge/“

I had a look at the ICA Commission on Map Design site and thought I would have a play with their WebMapperGPT tools. The idea is to describe the map that you want to build and then the AI tool will generate the code for you. Turned out it is both compulsive and a lot harder than I would have expected!

Jeremy spotted this in the Lemon Tree pub in London. He said “It was really interesting to interpret. Around 1850 we reckoned. The Crystal Palace is still in Hyde Park, no Tower Bridge, the terminus main railway stations are in.”

You might think “that’s really neat” then Ken chipped in to identify the maps as “Balloon View of London as seen from Hampstead by Henry Banks, 1851” – you could visit the original in the London Museum. For the Londoners trying to work out where Santa might be heading for his next delivery, remember that this map is north down (viewed from Hampstead looking south).

Geomatico nació allá por 2011 como un grupo de desarrolladores quemados del trabajo por cuenta ajena. Un grupo de personas que quería ser dueña de sus propias decisiones, cansada de estar supeditada a un modelo de trabajo con el que no se sentían alineadas.

Durante ocho años, Geomatico fue una red de autónomos autogestionada: personas independientes unidas en la toma de decisiones.

Hacia 2017 se planteó la necesidad de dar un salto y crear una estructura que nos permitiese acceder a determinadas ofertas a las que esta red de trabajadores independientes no podía llegar.

En ese momento decidimos constituir una sociedad mercantil para cubrir esa necesidad concreta. En aquella aventura solo dos de los miembros estaban disponibles y la opción viable fue crear una sociedad limitada.

Reinder said “I saw this brand new edition of Ulysses in a 2nd hand bookshop in Leiden. Quite remarkable I think, that this design with a Dublin town plan was not used earlier… or was it?”

Reinder spotted this poster for Billy Wilder’s 1953 film Roman Holiday nestled amongst underwear in a clothing shop in Rome

11/12/2025-17/12/2025

[1] Tableau de bord interactif permettant de suivre les efforts d’atténuation des catastrophes pour les récentes inondations et glissements de terrain de Sumatra © Tilikan Indonesia | Données cartographiques © Cartographes OpenStreetMap.

...

Elizabeth spotted this in a cafe opposite Gospel Oak station, probably Little Oak Coffee. Looks like both Kentish Town and this cafe are worth visiting.

Running in 2025 started out badly, but I hung in there, rode my bike and chugged on the elliptical machine when I couldn't run, did a lot of physical therapy, and finally got into good enough shape that I could plausibly try the Bear 100 mile race again.

Aspen, fir, and spruce trees bordering the Sinks area at the top of Logan Canyon. September, 2025.

I had little margin for error at the Bear, and misplayed my hand. I went out too fast and suffered for it after mile 35. I did manage to battle on for another 18 hours and 40 miles, and reached a new personal distance best. The best part of the whole event was the road trip with Ruthie, my crew chief, and staying with my aunt in Cache Valley before and after the run. And the fall colors. There were a lot of good parts. Crossing the finish line, sadly, was not one of them.

Another one from Reinder’s trip to Rome.

“Saw this textile work of art in Rome, in the National Gallery of Modern and Contemporary Art. It dates from 1990 and is made by  Alighiero Boetti” I had never heard of Boetti, it is worth clicking on the link to look at his Mappe series.

Disponible depuis mais 2025 en langue anglaise (voir les principales évolutions dans cet article), la version 3.6 d'ArcGIS Pro est désormais disponible dans différentes langues dont le français.