Nettles

While picking wild asparagus here in Sardinia yesterday I came across a very large patch of vigorous dark 'nettles' in and around an old ruined building. However they appear to have no stinging hairs on the leaves so I wondered - are these nettles or something else? Could I use them for cooking? Don't want to poison us... Anybody know? I will ask local people as well but they tend to be conservative in their foodstuffs and may not use nettles traditionally, although they do use wild finocchio, asparagi, bietole.