There doesn’t seem to be any consensus on this, or at least I can’t find it in the wiki. Many times I wanted to map military or police checkpoints, particularly in Yemen and Thailand. How do I do this? Can it be done so they show up on the Garmin maps produced by Lambertus (http://garmin.na1400.info/routable.php)?
The mkgmap default style translates nodes with barrier=border_control, which is used for some country borders. I don’t think it would be terribly wrong to use them for other checkpoints as well. There can be borders inside a country, say, around restricted areas.