From Vatican Radio:
The lights of theCupola atop St. Peter’s Basilicaare to go dark on the evening of Saturday, March 19th, along with those that illumine Bernini’s colonnade embracing St. Peter’s Square. From 8:30 PM to 9:30 PM in the evening, the lights shall remain dark on the occasion of the 2016 iteration of Earth Hour – an initiative promoted by the World Wildlife Fund International, in which the Vatican City State is participating. The lights illuminating the two fountains in the Square and the four candelabra surrounding the central obelisk will remain shining, however, along with those that light the two “arms” stretching from either side of the Basilica’s narthex and signed by the two great equestrian statues of Constantine and Charlemagne, north and south, respectively. The Press Office of the Holy See announced the specifics of Vatican City’s participation in the initiative, which were then reported widely on Friday in the Italian press.
More about Earth Hour at this link. And below is a video from the 2015 event.
Photo: Vatican Radio/AFP