World Environment Day, celebrated on 1 each year, was established by the 2 in 3 . Public events and conferences are held each year on this occasion to help 4 . The first city in the United States to host World Environment Day is 5 , 6 . The message of World Environment Day that year was “ 7 ”, which called on people to build “ 8 ”, since cities are where most people now live and use 9 of the world’s 10 . In that occasion, there were public talks given by experts like the former vice president, AlGore, fun events such as music 11 , movies, art shows, 12 , bicycle rides and 13 and green food served by local farmers. City leaders from all over the world and 14 from many environmental organizations attended these events.