I am perusing the internet since one day and still cannot find something satisfying.
The most important thing I am interested in is the speed limit (or an average speed) of the respective elements. I don't need information on small residential streets or city-level streets. Just the main road network would be enough. The extracted OSM stuff I downloaded from geofabrik.de or OSM extract Italy has tons of missing speed values and is thus not useful for me.
The closest I could get was the NASA SEDAC Global Roads Open Access Data. I subsetted on Italy via a GADM0 shapefile, it's slim, only with main roads, but there is no speed information.
I found this page with information on speed limits, but a manual editing would be virtually impossible.
Even a file that has consistent and complete (in the files I have, half of the roads go as "unclassified" - even though some of them are highways) information on the category of the street would be kind of o.k. In this case I could just impute average values for each type of street; which would be enough for the type of rough estimates of travel times I need.
Does anyone have a shapefile or information that could potentially help me?