30 Day Map Challenge

It Starts

This a summary of my 30 Day Map Challenge 2025. In a reckless moment on the 1^st November 2025 I thought I would have a go a making a few maps and see how far I’d get to before stoping. Some four-and-a-bit weeks later, this is what I got and the associated social-media Fosstodon toots.

Week 1

2025-11-01 Intro to the Intro

I can’t remember what motivated to do this. Or even what started this, other than I must have seem someone toot or post about the #30DayMapChallenge2025, and thoughts I could start and then give up when I felt like it.

2025-11-01 “Points”

In a vain attempt for #30MapsInAMonth here is a “Eurocentric” world map EPSG:3034 equal area projection using on WorldPopProject 1km² data showing projected population change between 2020 and 2030.

#30DayMapChallenge

A Eurocentric "world" map based on the EPSG:3034 equal area projection showing population change between 2020 and 2030 based on WorldPop data. White is areas of low or no population, the colour is then in population per km² with purple > -100*, grey between -10 and 10, green > 10, yellow > 100* that is a reduction

2025-11-02 “Lines”

For the second #30MapsInAMonth here is a map showing the heavy-rail network track-model and stations centred on the East Coast Mainline between South Yorkshire and the Fens. This uses the Rail Data Marketplace centre-line track-model published by Network Rail and the Office of Road and Rail (ORR) list of active stations.

#rail #network #stations #30DayMapChallenge #EveryoneHomeSafeEveryDay

A map showing the heavy rail network model as orange lines with stations as layers orange hexagons. The map centred on the East Coast Main Line between South Yorkshire and the Fens

2025-11-02 Outro to the Intro

As I then said at the time:

I’m never sure about this, but this year I decided to prepare for the #30DayMapChallenge by looking at things I have mapped over the years. My conclusion is I suffer from a rather myopic approach to the topic I visualise… #rail #Infrastructure #population #Europe

Followed by the revelation that there was a bit more to this than I had thought:

I’ve now discovered that there are meant to be “themes” for each day in the #30DayMapChallenge but as that’s beyond me, it looks like I will be running a #fringe event instead…

2025-11-03 “Polygons”

For the third #30MapsInAMonth are three theoretical European full-automated luxury high-speed heavy-rail network maps based on population distribution. This uses H3 hierarchical hexagon library to aggregate @WorldPopProject population data into #polygons, creating a maximum spanning tree network using population-to-population edge-weights and names for major urban centres added using @EUCommission Global Human Settlement Layer data.

#rail #network #HighSpeedRail #stations #30DayMapChallenge

A map of Europe showing a theoretical high-speed rail network based on population distribution. The high-speed lines are drawn in orange between named population centres with colour and line width proportional to the number of people who would use that route based on aggregating WorldPop population data into a more detailed set of h3 hexagons

2025-11-04 “Data”

For the fourth #30MapsInAMonth is a map also based on population distribution and the shortest walking route to routes from the 2021 Office for National Statistics census Output Area locations to the stations centred on Sheffield. The line width is proportional to the aggregated population and the routes are based on based on @openstreetmap path data, and the station locations on Office of Rail and Road (ORR) active station list

#rail #network #hinterland #stations #30DayMapChallenge

A map showing the shortest walking routes from the 2021 census Output Area locations to the stations near Sheffield, with Sheffield in the centre as orange lines. The line width is proportional to the aggregated population and the routes are based on based on the OpenStreetMap path and road data.

2025-11-05 “Earth”

For the fifth #30MapsInAMonth is a map global map of places called “Wayne” based on #OpenStreetMap. It is arguably both “Waynes World” and my most “excellent” map.

#PlaceNames #world #map #30DayMapChallenge

A global map of the world showing places called "Wayne" as points. Blue points correspond to streets, purple points correspond to political boundaries and red points correspond to geographical features

2025-11-06 “Dimensions”

For the six #30MapsInAMonth are two maps the one-dimensional population distribution of Austria. Aggregating @WorldPopProject@mapstodon.space population and country boundary data, based in 100m slices, this shows the relative population distribution in the horizontal and vertical points on the compass.

#population #Austria #30DayMapChallenge #OpenData

A map of Austria showing the political boundary in black with population orange colour density proportional to the fraction of total population in 100m East-to-West bands

2025-11-07 “Accessibility”

For the seventh #30MapsInAMonth are two maps showing the number of heavy railway services on week of 18 August 2025 for all stations within a 80km radius of the 20M Northern population centred around Leek in Staffordshire and the 22M South Eastern population centred on London.

#rail #PublicTransport #train #services #OpenData

A map showing heavy railway services as orange lines with the width proportional to the number of services that operated on week of 18 August 2025 for all stations within a 80km radius of the 22M South Eastern population centred around London. The line width is proportional to the number of services that operated.

A map showing heavy railway services as orange lines with the width proportional to the number of services that operated on week 18 August 2025 for all stations within a 80km radius of the 20M North and Midlands population centred around Leek in Staffordshire. The line width is proportional to the number of services that operated.

This was created using the Network Rail Common Interface File (CIF) timetable and centre-line network-model made available on the Rail Data Marketplace https://raildata.org.uk/

Although there is a similar population count within both areas there would appear to be a difference in provision of regional and urban heavy rail services between the two.

Week 2

In Media Res

After a week, it felt that revisiting maps and visualisations from over the last few years, this would be straightforward. Pride cometh before a fall.

2025-11-08 “Urban”

For the eighth #30MapsInAMonth maps are two maps showing the population density distribution in Europe based on the WorldPopProject 1km² populations dataset with scaled and the Global Human Settlement (GHS) data to scale labels on the diagram.

#urban #population #OpenData #30dayMapChallenge

A map showing urban population density as shades of orange for a given value of "Europe"

A map showing urban population density as shades of orange for a given values of "Europe" with scaled labels for urban centres based on urban population count

2025-11-09 “Analog”

For the ninth #30MapsInAMonth is a hand drawn map of the West Yorkshire metro public transport network. This shows urban centres around Leeds in black-ink hand-script on a brown paper bag. The locations and scaling are based on the Copernicus EEA Global Human Settlement layer (GHS) data.

#urban #Leeds #OpenData #30dayMapChallenge #PublicTransport

A hand-drawn map of Leeds and towns in vicinity (Bradford, Huddersfield and Wakefield) in black-ink on a brown paper bag showing the West Yorkshire metro public transport network. The text is scaled to the approximate population of the towns in the region.

I do wonder whether writing some names on a brown paper bag might be seen by some as a political act?

2025-11-10 “Air”

This first map doesn’t show the actual complexity of the electrification scheme in Britain as we have a myriad* of variants. Of which the majority of the network is without electrification (black), 25kV Overhead Line Electrification (OLE) (red) and 750V DC (dark green).

Unlike things to try in life, I think you should #ElectrifyAllThings but only once and with 25kV OLE.

A map of the British heavy rail network showing the myriad of* different electrification types with key. From the the majority of the network is without electrification (black), 25kV Overhead Line Electrification (OLE) (red) and 750V DC (dark green). * also known as 10

* thanks to Garry Keenor (@25kV@mas.to) for coordinating work to clean up the electrification tags on @openstreetmap@en.osm.town and agreeing the colour scheme used here.

2025-11-11 “Minimal map”

For the eleventh #30MapsInAMonth is an animated map of the British rail network showing track occupancy count for passenger train services in hour slices for the week of 18 August 2025.

This is based on the Network Rail centre-line track- or network-model and Common Interface File (CIF) format timetable file published on the Rail Data Marketplace combined with ORR and @openstreetmap@en.osm.town location data for timetable points.

#OpenData #30dayMapChallenge #timetable #rail #passenger

An animated map of the British rail network showing track occupancy count for passenger train services as orange lines with width proportional to the service count in hour slices for the week of 18 August 2025

2025-11-12 “Map from 2125”

For the twelfth #30MapsInAMonth is a theoretical future public transport network for a hundred years hence. This is based on population density aggregating @WorldPopProject@mapstodon.space population data onto 43km edge-length hexagons, creating a network flow and overlaying with @CopernicusEU@respublicae.eu urban centre data. The different population centre colours related to different levels of urbanisation.

#OpenData #30dayMapChallenge #population #PublicTransport #passenger #future

A future public transport map for 2125 showing land in light blue, network links in orange width proportion to flow and population centres increasing density in yellow, and cyan.

2025-11-13 “10 minute map”

For the thirteenth #30MapsInAMonth are two short form maps based on Tom Forth’s https://www.tomforth.co.uk/circlepopulations/ tool that shows the population within a 100km radius circle of two points in the UK: a point in the North is 20 141 911 and West London is 22 625 112. This is based on @opendatabund@social.bund.de Street Map data and @CopernicusEU@respublicae.eu EU Global Human Settlement (GHS) layer centre data.

#Population #UK #OpenData #30dayMapChallenge #NorthSouth

A map showing OpenStreetMap and EU Copernicus GHS data for a 100km radius circle around a point near Leek, in Northern England that has a population 20 141 911.

A map showing OpenStreetMap and EU GHS layer data for a 100km radius circle around a point near West London, that has a population 22 635 112.

2025-11-14 “OpenStreetMap”

For the fourteenth #30MapsInAMonth is a map showing high-speed rail, or not, for a given value of “Europe”. This is based on line-speed from OpenStreetMap tagged data. The geography is from the WorldPopProject 1km² dataset.

A map of Europe showing high-speed rail with land in white, sea in light blue. High-speed tail lines are orange or otherwise in black.

Week 3

Zeno all the way down

This is half-way point, the point where easy visualisations were done, 15-days left and eight* where I had no idea. Not a clue. Leaving just me and the turtles…

* “Black”, “Makeover”, “Water”, “Icons”, “Out of this World”, “A new tool”, “Cell” and “Fire” were very much WTAF

2025-11-15 “Fire”

For the fifteenth #30MapsInAMonth are two sets of map for electrical power transmission mostly on the Islands of Northern Europe.

Based on OpenStreetMap, the first set show the high-voltage transmission cables and lines, and then second of these with wind-turbines.

The second set shows #OpenData from @nationalgriduk@bird.makeup and Scottish and Southern Electricity Networks (SSEN) data. 1/n

#electricity #transmission #generation #Ireland #GreatBritain #30dayMapChallenge

A map showing the high-voltage electricity grid for the islands of Northern Europe and transmission tower locations. The blue diamonds show tower locations, the coloured lines either overhead lines if on a tower, or cables if not. The line colour from green to yellow indicates increasing transmission voltage.

A map showing the high-voltage electricity grid for the islands of Northern Europe with transmission tower and wind-turbine locations. The blue diamonds show tower locations, the grey square wind-turbines, the coloured lines either overhead lines if on a tower, or cables if not. The line colour from green to yellow indicates increasing transmission voltage.

A map showing National Grid power lines in orange, cables in dark green and towers as blue diamonds.

A map showing National Grid and Scottish & Southern Electricity Networks power lines in orange, cables in dark green and towers as blue diamonds.

The gap in the central belt of Scotland is because I could not find the equivalent data from the operator SP Energy Networks. If this is available, I would be happy to update the map.

2025-11-16 “Cell”

For the sixteeth #30MapsInAMonth are two map showing the watershed shortest walking route to the heavy rail stations in Britian. This uses @openstreetmap@en.osm.town highway, road and path data for routing, scaled to show the number people who might take that path.

The first shows routes based on @WorldPopProject@mapstodon.space 1km² data The second shows routes based on data from the UK #Census2021

#Rail #Passenger #PublicTransport #GreatBritain #OpenData #30dayMapChallenge

A map showing the walking routes from the 1km^2^ WorldPop 2025 population locations to heavy rail stations in Britain as orange lines with width scaled to the aggregated number of people on that route

A map showing the walking routes from the 2021 census population Output Area/Data Zone locations to heavy rail stations in Britain as orange lines with width scaled to the aggregated number of people on that route. The Census data is from Office of National Statistics and Library of Scotland

2025-11-17 “A new tool”

For the seventeenth #30MapsInAMonth are four maps revising rail electrification using Vega-lite https://vega.github.io/vega-lite/, a tool I had never used before the weekend.

As before, this uses tagged @openstreetmap@en.osm.town railway data, but this uses a topological (TopoJSON) version, which can then be quantised to give different levels of granularity.

#Rail #Electrification #PublicTransport #Vega-lite #GreatBritain #OpenData #30dayMapChallenge

A map of the Islands of Northern Europe at a medium level of simplification showing heavy rail electrification. No electrification is in black, Overhead Contact Line (OCL) in red, other forms of electrification in green and dual electrification in orange.

A map of the Islands of Northern Europe at a high level of simplification showing heavy rail electrification. No electrification is in black, Overhead Contact Line (OCL) in red, other forms of electrification in green and dual electrification in orange.

A map of the Islands of Northern Europe at a lower level of simplification showing heavy rail electrification. No electrification is in black, Overhead Contact Line (OCL) in red, other forms of electrification in green and dual electrification in orange.

A map of the Islands of Northern Europe with a limited level of simplification showing heavy rail electrification. No electrification is in black, Overhead Contact Line (OCL) in red, other forms of electrification in green and dual electrification in orange.

These maps then available online here

Medium simplification

High simplification

Lower simplification

Limited simplification

With more time, it should be possible to make them zoomable and interactive.

2025-11-18 “Out of this world”

For the eighteenth #30MapsInAMonth are a set of four animated simulations of a three body solar system. Where the mass of the two planetary bodies and the initial offset angle is varied, and correspond to the three numbers at the top of the simulation.

This was inspired by my daughter’s final year degree project and, although rare, shows how you can have some things go spectacularly wrong sometimes, or not.

#Space #Modelling #Chaos #python #30dayMapChallenge

An animated simulation of a theoretical solar system with two planets showing the trajectory of the two planets as red and green arcs and the central mass as a blue cross. In this video the chaotic movement of the two planets causing the two planets to collide.

2025-11-19 “Projections”

For the nineteenth #30MapsInAMonth are a set of map using different coordinate system projections of Natural Earth railway data https://www.naturalearthdata.com/

The four maps represent points on the oblate-spheroid that is the Earth on a surface. The first uses latitude and longitude in °, the rest are in meters. The second is commonly used on the web, the third a projection for Europe and the final is the UK Ordnance Survey map projection.

#rail #WorldMap #NaturalEarth #Coordinates #30dayMapChallenge

A projection showing heavy rail lines as orange lines on a world map using base latitude and longitude coordinates projection EPSG3857 in °

A projection showing heavy rail lines as orange lines on a world map using a Pseudo-Mercator projection EPSG3857 in m

A projection showing heavy rail lines as orange lines on a world map using a Europ-centric projection EPSG3034 in m

A projection showing heavy rail lines as orange lines on a world map using the Ordnance Survey UK-centric projection EPSG27700 in m

2025-11-20 “Water”

For the twentieth #30MapsInAMonth are a set of map using @openstreetmap@en.osm.town and @ordnancesurvey@bird.makeup Survey to look at rivers and streams in the Islands of Northern Europe.

These three maps show difference scales and how different tags affect the maps.

#water #rivers #WorldMap #OpenData #30dayMapChallenge

A map of OpenStreetMap data for Great Britain and Ireland showing rivers as blue lines

A map of OpenStreetMap data for Great Britain and Ireland showing rivers, streams and canals as blue lines

A map of OpenStreetMap data for Wales showing rivers, streams and canals as blue lines

The final two maps then overlay the OSM and OS data to see how they compare.

A map of OpenStreetMap data for Great Britain showing rivers, streams and canals as blue lines and Ordnance Survey Open River data as golden lines

A map of OpenStreetMap data for Wales showing rivers, streams and canals as blue lines and Ordnance Survey Open River data as golden lines

2025-11-21 “Icons”

For the twenty first #30MapsInAMonth are two maps showing concerts played by the experimental music group Einstürzende Neubauten using the band icon.

The two maps show all concerts in European and the world and is based on geolocation using data from https://www.fromthearchives.com/en/chronology1.html.

“You will find me if you want me in the garden, unless it’s pouring down with rain.”

#EinstürzendeNeubauten #TheGarden #Europe #WorldMap #OpenData #30dayMapChallenge

A world map with land in bronze and sea in white showing locations of Einstürnzende Neubaten concerts using the Einstürnzende Neubaten petroglyph

A map of Europe with land in bronze showing locations of Einstürnzende Neubaten concerts using the Einstürnzende Neubaten petroglyph

Week 4

Intro to the Outro

It was at this point that I could then see the end and had something prepared for everything outwith “Black” and “Makeover”. Which was a relief, especially when I got a steer on “Black” based on air-pollution data from the UK National Atmospheric Emissions Inventory.

My thought for the “Makeover” was to then redo the Fully Automated Luxury European High-Speed Railway from 2025-11-03 but went with a recut with a global electrification map, of the . Which was more popular then the theoretical high-speed rail map, and vox populari vox dei and all that.

2025-11-22 “Natural Earth”

For the twenty second #30MapsInAMonth are three maps showing Natural earth data.

The first map show the 10m urban layer for the low countries, the second two the Islands and Northern Island and Europe with heavy rail lines.

#NaturalEarthData #Europe #Population #OpenData #30dayMapChallenge

Natural Earth Data urban 10m population data for the low countries coloured in viridis by zoom level. Which seems to link to population density

Natural Earth Data urban 10m population data for Europe coloured in Viridis by zoom level. Which seems to link to population density, plus rail lines in orange

Natural Earth Data urban 10m population data for the Islands of Northern Europe coloured in Viridis by zoom level. Which seems to link to population density, plus rail lines in orange

2025-11-23 “Process”

For the twenty third #30MapsInAMonth here is are two talks about the intent and give some details as to how a number of visualisations were made.

Here are #OpenData resources used in these visualisations

The first is a Leeds Digital festival talk about a fully automated European luxury high-speed railway

The second is about visualisation of Office of Rail and Road data

#WhyDoIMakeMaps #30dayMapChallenge

2025-11-24 “Places and names”

For the twenty fourth #30MapsInAMonth here is a map that shows the stations where the aggregated number of people living within the shortest walking distance to a heavy rail station is greater that 50k. The station name is scaled based on this aggregated number.

#Passenger #Rail #ShortestTravel #Station #30dayMapChallenge

I find it interesting that, although there is a higher population in the South East and North West, this would suggest relatively fewer stations serving the population along the route of the Midlands Main Line (MML) or in the North East around the Tyne and Tees.

2025-11-24 Hardest Visualisation

This visualisation caused the most debate its means, where I found it useful to refer to the post where

(It’s based on a dataset where I worked out the shortest walking distances from the OA census and/or WorldPop 1km² centroids data to heavy rail stations to end up with a watershed diagram as shared earlier If you then add up the population served by station and rank them, you get this…)

2025-11-25 “Hexagons”

For the twenty fifth #30MapsInAMonth are a series of six maps showing WorldPopProject 1km² population data aggregated into a hierarchical set of scaled hexagons.

Wordlpop European population density scaled in shards of orange aggregated into hexagons

Here are some more at increasing levels of granularity.

2025-11-26 “Transport”

For the twenty sixth #30MapsInAMonth is a visualisation using the Office of Rail and Road (ORR) Financial Year 2018/19 to 2023/24 passenger travel data projected onto a Network Rail shortest-path network using the centre-line track-model to create visualisation for passenger journey numbers for the active rail stations across the British rail network.

#Passenger #Rail #ReproducibleCode #30dayMapChallenge

An animated map of passenger travel by financial year in Britain showing land in dark green, sea in light blue and scaled aggregated passenger numbers as white lines with a description in sans serif stating the year

Individual visualisation for the 2 587 stations on the mainline network are available here the code to generate this is here

2025-11-27 “Boundaries”

For the twenty seventh #30MapsInAMonth is an animation showing the organisational operational boundaries boundaries of Network Rail using FOI data in a jazzy shaded colour scheme. This shows region, route, maintenance delivery unity and TME*.

* if truth be told, I don’t know what a TME is…

An animated hierarchical map of the organisational operational boundaries of Network Rail as black lines and shading from route, region, maintenance delivery units and beyond.

2025-11-28 “Black”

For the twenty eighth #30MapsInAMonth are two visualisations based on the UK National Atmospheric Emissions Inventory (NAEI) showing total and transport air pollution and emissions.

#AirPollution #Emissions #OpenData #30dayMapChallenge

A map of the UK showing atmospheric pollution in black using the NAEI 2023 all pollution dataset.

A map of the UK showing atmospheric pollution in black using the NAEI 2023 land transport pollution dataset.

2025-11-29 “Raster”

For the twenty ninth #30MapsInAMonth are two visualisations based on the WorldPopProject 2030 projected population as 100m² raster data. The first shows the population of the Islands of Northern Europe and the second population change.

#Raster #Population #Beethoven #GBR #IRE #OpenData

A map showing the population density of the UK and Ireland in shades of orange.

A map showing predicted population density change in the UK and Ireland between 2025 and 2030 in Viridis where darker colours are population reduction and lighter green or yellow indicate population growth

To provide a European perspective, if you would like a nine minute video of all the WorldPop raster data for all the countries in Europe, for a given value of “Europe”, ordered by three letter ISO code to the second movement (“Molto Vivace”) of Beethoven’s ninth symphony, here you go

2025-11-30 “Makeover”

For the thirtieth* #30MapsInAMonth are maps showing the electrification of the global heavy-rail network based on the track-model and electrification and electrification tags from @openstreetmap

An electric railway is the least carbon-intensive way of moving freight and passengers over long distances**. More so where the electricity generation is from renewable sources.

* and final

** words chosen more carefully

#Decarbonization #Electrification #OpenData #30dayMapChallenge #PublicTransport

While my plan was to make a global full-automated luxury high-speed railway for the final day, I chose to makeover the electrification maps because they seemed to be of most interest to people.

Outwith the ORR ODM data map and they will get updated once next FY year’s data is published…

How It Ends

This has been hard work and probably took up more time than it should have. Equall I did bigger things than I had thought I could. But quite a lot of what I first thought I would post I haven’t. Often because it didn’t fit the theme.

I also found myself at a point about a half-way-through where I decided to get stuff made ahead of time. Which was good as it meant I finished the whole piece and had things to say each day that vaguely fitted the theme. However, this didn’t help with the actual daily posting itself.

This is hard, as a combination of social-media file-size and resolution limits, my inability to articulate what it is that I have just done in words, a wish to post insanely large images and the general yak-shaving of getting animations to work was probably trickiest bit for me. No fun.

But this is where I am now

After a brief period of activity, where I have posted a lot of maps for a month, I now plan to return to my usual approach of mostly ignoring posting anything unless I really have to.

Making things that are nice to look at, learning new stuff, and the general interaction and feedback kind makes it worth it though.

TL;DR some people liked it and I learnt some stuff. Maybe that’s enough.