In the 1969 UNESCO Conference in San Francisco, peace activist John McConnell proposed a day to honour the Earth and the concept of peace. The first such event was celebrated on March 21, 1970 to coincide with the first day of spring in the northern hemisphere. A month later the United States Senator Gaylord Nelson proposed the idea to hold a nationwide environmental teach-in on April 22, 1970. This first celebrations took place in more than two thousand colleges and universities, ten thousand primary and secondary schools, and hundreds of communities across the United States. It brought over 20 million Americans out into the spring sunshine for peaceful demonstrations in favour of environmental reform and protection. The 22nd of April subsequently
became the new date for the International Earth Day.