Equinox Earth Day is observed worldwide on March 20, celebrating environmental protection and honoring the Earth. This event was proposed by peace activist John McConnell in 1969 at a UNESCO Conference in San Francisco, with the first celebration occurring in 1970. The observance coincides with the spring equinox in the northern hemisphere and is supported by the United Nations, with UN Secretary-General U Thant signing a proclamation in 1971. A traditional custom includes ringing the Japanese Peace Bell, a symbol of peace, which takes place in many major cities around the world. The event is one of two major Earth Day celebrations, the second occurring on April 22.