Watch Robert Pattinson in “The Lost City of Z” in Italian cinemas from 22 June 2017
Leone Film Group updated their website today and now shows the Italian release date has moved from April to 8 June 2017.  Hope this date sticks.
 
Updated release details after the cut
UPDATED: 3 May 2017
According to Coming Soon (Italy) and Eagle Pictures who are releasing with Leone Film Group, the release date is now 22 June 2017.
They have also shared the Italian promo poster
