How do you make all building indestructable?

As the title suggests, how do you make buildings indestructable as the roads and farms are?

I believe that by adding the "hinterland" prefix to the name you can make buildings indestructible, though they can still be damaged. (Note that roads mines and farms are named hinterland_roads, hinterland_farms, and hinterland_mines in EDB).

That is correct - 'temple' is another word that defines properties; note that these are the tree names.

Search for building's entry in one of the text files in rome/data/descr_building_battle/ and edit it so it'd look similar. Example of indestructable building you can walk trough entry:

pavement_bath_house
{
stat_cat indestructable ;; <- noticed? :)
localised_name none
level
{
min_health 0 ;; <- remember about that
battle_stats
item pavement_bath_house
physical_info none ;; <- so you can walk trough it. If you want to keep collision just leave this line as it was before.
}
}

Hope it helps. :)

Thank you gentlemen for your excellent advise!