I downloaded a shapefile for Montenegro from https://gadm.org/download_country_v3.html and created a table in PostGIS using
shp2pgsql. The table has column
geom of type
geometry which is a multipolygon. I'm drawing these multipolygons as polygons using Leaflet.draw (converting multipolygon to single polygon is the reason why some municipalities in the south with islands have strange boundaries).
As you can see data from shapefile isn't correct (especially in the north). I'm using OpenStreetMap as basemap provider, so the map images are correct. Also to prove GADM data isn't correct, here is the image of the most eastern municipality on their website https://gadm.org/maps/MNE/rozaje.html.
It's clearly the same shape as the one on the map. I don't mind shapes not being too detailed or slightly incorrect, but I would like at least their positions to be accurate. Each of the municipalities in the north is moved like 10 km to the south.
Please share if you know a better source for this type of data.