http://www.pcn.minambiente.it/viewer/
This is quite a handy website, which allows you to select 1:25000 scale topo map overlays for virtually all of Italy, as far as I can see.
Since everything is in Italian, I've taken a screenshot showing what should be selected in order to view the 1:25000 maps:
This is quite a handy website, which allows you to select 1:25000 scale topo map overlays for virtually all of Italy, as far as I can see.
Since everything is in Italian, I've taken a screenshot showing what should be selected in order to view the 1:25000 maps: