OSMOSIS Multipolygon tagg

Ill use this command to extract everything with the tagg snowmobile.

osmosis --read-pbf sweden-latest.osm.pbf --tf accept-ways snowmobile=* --tf reject-relations --used-node --write-xml snowmobile.osm

Everything works fine but got one problem. Multipolygon area with the tagg snowmobile are missing. Ill hope someone can help me figure how to get this multipolygon areas by using the tagg snowmobile.

The multipolygons are missing because you’ve used “reject-relations”. Multipolygons are relations.

I have tried without reject-relations but i still dont get this areas. When i dont use reject-relations i got many nodes i dont want (like bus stops and railway stops)

Here is one example area