DBSN (DataBase di Sintesi Nazionale) is a database containing the most significant territorial information in Italy. It is developed by IGM (Istituto Geografico Militare) and is available in ODbL, as stated on its website. For reference, here’s the DBSN page on OSM wiki.

Since municipality borders in Italy were updated last time in 2001 using ISTAT (Istituto Nazionale di Statistica) data, and since these are open data, I think it’s time to update everything in the right way.

With the help of dsantini’s very useful scripts, I will download boundaries data for one province at a time (starting in Abruzzo, my home region), and then I will continue in alphabetic order.

This project will start on Dec 2025/Jan 2026. I really don’t know how much it will take me, there are 7’896 municipalities in Italy.

Here’s how I will work:

1. download boundaries data for the whole province
2. opening them in JOSM
3. in order to preserve history/chronology, I will modify existing boundary lines/ways modifying nodes position and adding nodes when/where needed
4. I will use dsantini’s map with all DBSN municipality borders for reference to where multiple lines are connected
5. I will only touch borders on land, I won’t touch borders between land and sea
6. I will hopefully make one changeset per completed municipality

I will add below the list of provinces I’ve completed, with the number of finished municipalities for each province:

• Chieti (0/104)

Lots of love, damianeue, mapper since 2019