Administration boundaries

What’s the right way to define them?

  1. Using existing ways (highways, waterways, etc) to delimitate a boundary and then defining a relation over thus ways
  2. Drawing a physical line overlapping existing ways and then adding the attributes to this line

Appreciate your help since we are going to start defining them in Argentina and we would like to do it correctly

already seen and including the discussion pages in the OSM wiki?

Maybe when you won’t get sufficient answers here, aks your problem at … I think this is a general question that is interesting for all users.

Personal opinion: 1 is vastly preferable. It makes editing much, much easier and in OSM we optimise for the mapper.

I would add that you should use method 1 only when you know how the boundary is legally defined. In my part of the world, I come across many admin boundaries on the map, but I have no clue if they’re defined relative to any physical objects. In some regions, the admin boundaries are fixed by the original definition, and do not change if a highway or river is rerouted.