OpenStreetMap is (sometimes) a handy database of military and police locations – here’s how to see them

OpenStreetMap – 70,641 objects are tagged with “landuse=military”. Source: TagInfo, 6 July 2018

Most of the time we use OpenStreetMap (OSM) as a gazetteer; that is, a means of representing the geographical aspects of Security Force Monitor’s data.

For example, our research indicates that the Mexican army unit 105 Batallón de Infantería had a base in Frontera, Coahuila, Mexico from 24 February 2014. To geocode this data we will search OSM to find the nearest “object” to the named settlement – in this case a “node” called Frontera (ID number 215400772)  – and link it to the unit as a base. Our Research Handbook contains the rules we use for doing this.

When we publish the data on it will be displayed in the “Sites” section of the record for 105 Batallón de Infantería along with all the sources that evidence it:

overpassblog1 sites for 105 Batallón de Infantería, Mexico

So far we have found OSM to be a good enough gazetteer. And it’s free. And it’s open licensed. And we can fix it if we need to. So you won’t find us moaning and whinging.

However, OSM has a number of issues with accuracy, coverage and change over time so we do not use OSM as a primary source of information. Instead we use it as one of a number of sources of lead information which help us piece together the geographical footprint of a security force. It’s why, for example, we don’t place 105 Batallón de Infantería directly at Venustiano Carranza International Airport, even though this is the case on OpenStreetMap. We don’t (yet) have other sources to evidence this, but OSM gives us a useful prompt to investigate this further.

I’ll cover the pros and cons of using OSM in our research in a future blog post but for now I’d like to talk about how we OSM in the early stages of research into a security force.

OSM is a useful tool for getting an impression of a security force’s physical infrastructure: lead information about where it may have bases and facilities, and the terrain that may be reserved for use by security forces  (like firing ranges,  training areas, ). How do we do this?

OpenStreetMap is a database

The points, lines and polygons (“objects”) you see on OSM are described with “tags”: for example, a tag can define a line as a “road” or a shape as a “building”, and give it a name. Incredibly, on OSM there are  over 70,000 different ways to describe an object, but the tag we’re interested is “landuse=military”.

OSM currently has 70,641 objects to which the tag “landuse=military” has been applied. OSM’s own documentation about this tag is here. The tag can be refined further by applying another tag called “military=[something]” – the [something] in question can be values like the below:

  • military=airfield
  • military=barracks
  • military=bunker
  • military=checkpoint
  • military=training_area

There are currently over 290 additional tags used on OSM to increase the specificity about the type of military land use.

How can we use this information to aid our research? The usual need we have is for a BIG LIST that we can simply go through one by one and use as starting points for searches or to cross reference data we get from other sources. Although we can view these items on OSM we can’t get such a BIG LIST. To do this we need to use a way of accessing OSM’s data called Overpass API. This is mostly by programmers but for us patient non-programmers there is a slightly easier way to use this API – it’s called  Overpass Turbo.

Using Overpass Turbo to show military land use on OSM

So, here goes. Let’s ask OSM what objects in Mexico are tagged with “landuse=military”.  Head over to Overpass Turbo:

After opening that link copy the below into the input area on the left-hand side and then hit the “Run” button (top left):

// Limit the search to “Mexico”
// Pull together the results that we want
 // Ask for the objects we want, and the tags we want
// Print out the results
out body;
out skel qt;

What’s this then? Yes, it’s a map of just those objects tagged with “landuse=military”:

Overpass Turbo – map of objects tagged “landuse=military” in Mexico (live)

Exciting! You can export this into a common geographical format (like KML or geoJSON). But I said we needed a list. Let’s alter the query a bit. Try putting this into the editor:

// Get a CSV output
[out:csv(name, "tags:name:es", "tags:name:en", ::"type", ::"id", ::"lat", ::"lon";true;",")][timeout:25];

// Limit the search to “Mexico”
// Pull together the results that we want
 // Ask for the 
// Print out the results
out body;
out skel qt;

Same data, but in a list that we throw into a spreadsheet to work more on:

Overpass Turbo – CSV list of objects tagged “landuse=military” in Mexico (live)

Even the snippet above gives us some unit and facility names to research further, as well as the locations of possible facilities that perhaps someone with local knowledge has flagged as being used for military stuff.

The queries above can be altered to search within different countries or other defined areas, examine different tags (like “amenity=police”… give it a try), and export more data (such as an object’s history).

Wrapping up

  • As well as being a map that we can search, OpenStreetMap is a database that can we query in depth.
  • Historical and contemporary military and police locations may be identified inside OpenStreetMap using the “landuse” tag. More information about the tagging system can be found on OSM’s own TagInfo service.
  • Using Overpass Turbo we can pull out that information as use it as lead information during our research. Overpass Turbo is free to use, and can output  maps and lists. The Overpass query language is documented here and there are some super examples on the OSM wiki here.

I’m sure there are more elegant ways to use Overpass Turbo than my basic code, so should anyone wish to help us out  I’m all ears (tom [at] We’re also interested in improving the data on military and police facilities that exists in OSM, … but that’s another post.

I hope this has been a helpful read, and do comment, respond and correct as needed.

Not all snapshots are created equal – a time-saving Wayback Machine technique

We’re going to write about our daily work more often.  I’ll go first with a nerdy research tip:

The Internet Archive’s Wayback Machine (the awesomeness of which I won’t bang on about) can show you when captures of the same page differ in some way from each other.

So what?

Here’s a long dead page used by La Secretaría de la Defensa Nacional (SEDENA) in Mexico to list the commanding officers of Zonas Militares (a major tier of the army in Mexico).

It exists only in the Internet Archive’s Wayback Machine now. Here are two captures of that URL – made in 2004 and 2005 respectively . The screenshots below show only the first 10 entries (of over 40 in each). Can you spot the difference?

Clipping from 8 February 2004 Wayback Machine snapshot of SEDENA army commanders page
Clipping from 3 October 2005 Wayback Machine snapshot of SEDENA army commanders page

Although the archived URL is the same, the content is not. For example, in the February 2004 snapshot SEDENA lists “Noe Antonio Ordoñez Herran” as the commander of 1/a Z.M. However, by October 2005 SEDENA lists “Germán Redondo Azuara” as the commanding officer. This is a substantive difference that we want to capture; there are also other differences between these two snapshots.

How do we approach it? First, we establish the total number of snapshots. Helpfully, the Wayback Machine tells us this for any URL that it holds snapshots for. For example, the present SEDENA page was captured 57 times:


It is likely that a page like this may have been updated regularly: the little bar chart tells us that there are differences in the sizes of the snapshots, indicating that something changed. The changes could be an update to the text in the list of commanders,  a design change of some sort that affects the page size.

Do we have to wade through all of them to find out what the differences are? No. The Wayback Machine can tell us which snapshots differ from the previous ones. Therefore, we can just go to those that differ in some way from the others and extract information from those.

To do this, we have to use another way to ask the Wayback Machine questions: the Wayback CDX server. The CDX server is a more advanced way to query the Wayback Machine, but also using your browser. It doesn’t have graphical user interface to browse the archived pages. Rather it provides metadata about the snapshots.

Here’s Wayback Machine data about our URL, but viewed from the CDX server:

Some output from the Wayback Machine CDX server.

Here’s the URL that gives you those results:

This is the few rows of the same 57 results but shown as metadata rather than as a navigable, graphical version of the web captures themselves. I’m sure you can figure how out how to turn this list into a spreadsheet that you can use to organise your research (hint: copy-paste into your favourite spreadsheet, then text-to-columns using a space as the separator).

By changing the URL a bit we can filter out snapshots that are the same as the preceding one:

We’ve tacked on two new bits to the end of the query URL:


This shows which of the snapshots have duplicates. And then:


This has the effect of removing data about snapshots that are the same as the previous one.

Overall, our results are filtered from 57 down to 31 snapshots. It’s removed 26 that were the same as the preceding one and saved us a good hour of work.

As it happens, of those 31 snapshots only 12 hold content that is useful to us. The remainder are captures of server errors, because SEDENA changed its official website (and URL structure) four times between 2004 and 2017. But that, my friends, is another blogpost.

So, to wrap up:

  • The Wayback Machine has the equivalent of an advanced query that helps us find out when snapshots of the same page differ from each other.
  • It’s called the Wayback CDX server, and you can read more about what it does on its Github page.
  • Using it at the beginning of a bit of research can save you a lot of time.

I hope this helps some of you save time when trawling the Wayback Machine, and encourages you to experiment a bit with obscurer features of well known tools. It certainly helps us create the rich data you see on




Prosecutor of the International Criminal Court receives complaint of crimes against humanity by the Mexican Army

Earlier today the Mexican Commission for the Defense and Promotion of Human Rights (CMDPDH), the International Federation for Human Rights (FIDH) and other partners submitted a complaint to the Office of the Prosecutor (OTP) of the International Criminal Court (ICC). In their report they allege that between 27 March 2008 and 16 January 2010 in the Mexican State of Chihuahua the Mexican Army committed crimes against humanity that fall under the jurisdiction of the ICC.

The complaints allege that military units operating as part of “Operation Conjunta Chihuahua” – a large and complex operation established to combat organized crime as part of the so-called “war on drugs” – committed the crimes of murder, torture, rape and sexual violence of comparable gravity, and enforced disappearances. Further, they allege that far from being isolated incidents these crimes were committed as part of a widespread and systematic attack on the civilian population, pursuant to a known and tolerated state policy, and hence should be considered crimes against humanity within the definitions of the Statute of the ICC.

Security Force Monitor is not a signatory of this complaint, but is honoured to have provided research support to CMDPDH during the course of their investigation into these events. Through a close read of existing public records we were able to provide a detailed look at the composition, chain of command and areas of operation of Operation Conjunta Chihuahua, in particular its relationship to Region Militar XI. Our full contribution to CMDPDH’s investigation is not publicly available and has been included as a confidential annex to the ICC complaint. However, on we have already published on much of the data produced about Operation Conjunta Chihuahua along with data on over 1000 units and 300 commanding officers of the security forces of Mexico going back a decade.

Now the complaint has been submitted the Office of the Prosecutor is obliged to assess it and move to start an investigation if it finds there is a reasonable basis to do so. We hope that the Prosecutor is persuaded by the complaint and we will track developments here on the blog. The full communication is available in Spanish from CMDPDH and English from FIDH.

En español:

Fiscal de la Corte Penal Internacional recibe denuncia de crímenes de lesa humanidad cometidos por el Ejército Mexicano

El día de hoy la Comisión Mexicana de Defensa y Promoción de los Derechos Humanos (CMDPDH), la Federación Internacional de los Derechos Humanos (FIDH) junto con otras organizaciones colaboradoras, presentaron una denuncia ante la Oficina del Fiscal (OTP) de la Corte Penal Internacional (CPI).  Dentro de su informe, se denuncia que entre el 27 de marzo de 2008 y el 16 de enero de 2010 en el estado mexicano de Chihuahua, el Ejército Mexicano cometió crímenes de lesa humanidad que caen bajo la jurisdicción de la CPI.

Las denuncias alegan que las unidades militares que operaban dentro de la denominada “Operación Conjunta Chihuahua” (una compleja operación militar establecida para combatir el crimen organizado como parte de la llamada “guerra contra el narcotráfico) cometieron los crímenes de asesinato, tortura, violación y abuso sexual y desapariciones forzadas. Además, alegan que, lejos de ser incidentes aislados, estos crímenes fueron cometidos como parte de un ataque generalizado y sistemático contra la población civil, de conformidad con una política estatal conocida y tolerada por el Estado, y por lo tanto deben considerarse como crímenes de lesa humanidad dentro de las definiciones del Estatuto de la CPI.

A pesar de no ser un signatario de dicha denuncia, el Security Force Monitor tiene el honor de haberle brindado análisis de apoyo a la CMDPDH durante el transcurso de su investigación. A través de un análisis minucioso de los registros públicos existentes, pudimos proporcionar una visión detallada de la composición, cadena de mando y áreas de operación de la Operación Conjunta Chihuahua y en particular su relación con la Región Militar XI. Nuestra contribución total a la investigación de CMDPDH no se encuentra disponible públicamente y se ha incluido como un anexo confidencial a la queja presentada ante la CPI. Sin embargo, en ya hemos publicado muchos de los datos producidos sobre la Operación Conjunta Chihuahua junto con datos de más de 1000 unidades y 300 comandantes de las fuerzas de seguridad de México que datan de hace una década.

Ahora que la denuncia ha sido entregada, la Oficina del Fiscal se encuentra obligada a evaluarla y proceder a iniciar una investigación si considera bases razonables para hacerlo. Esperamos que el Fiscal sea persuadido por la queja y tome las medidas adecuadas, a las cuales daremos seguimiento en el presente blog. La comunicación completa se encuentra disponible en Español en el portal de la CMDPDH y en Inglés en la página de la FIDH.