At approximately 11:00 AM on April 6, 1966, students and staff at Westall High School and the adjacent Westall State School in the Melbourne suburb of Clayton South, Victoria watched as a silver-grey, cup-shaped object descended from cloud cover and passed low over their playing fields. Estimated to be roughly fifteen metres across, the craft briefly landed in an open paddock just beyond the school's boundary known as 'The Grange,' then rose again and, accompanied by five Royal Australian Air Force aircraft that arrived afterward, departed toward the southeast. More than two hundred children, a dozen teachers, and multiple residents of Clayton South, Huntingdale, and the surrounding suburbs observed the incident.
Teachers who ran with students to the landing site reported a circular patch of scorched, flattened grass where the object had rested. Within hours, official personnel — described variously as military or government officials in uniform — arrived and roped off the area. Students were instructed not to speak of what they had seen, and at least one teacher reported that a formal order came down from the Department of Education discouraging discussion of the event.
Local press coverage appeared briefly in The Dandenong Journal and The Age of Melbourne, but the case quickly dropped out of the news. It was not until the 2000s that researcher Shane Ryan and documentary-makers traced and interviewed surviving witnesses. Many of the former students — now adults — described having carried the memory in silence for decades, and several had suffered career consequences for attempting to speak publicly about it in the years immediately after.
A memorial park was eventually established at the former landing site, and in 2010 the state of Victoria released its historical archive of Westall documents. The Westall encounter is the largest mass UFO sighting in Australian history and one of the best-documented daylight cases anywhere to involve landing traces, multiple military vehicles, and hundreds of child witnesses.