Jamboree on the Air (JOTA)
From their site:
What is JOTA?
When Scouts want to meet young people from another country, they usually think of attending a World Jamboree. But few people realize that each year more than 400,000 Scouts and Guides “get together” over the airwaves for the annual Jamboree-on-the-Air (JOTA). Modern technology offers Scouts the exciting opportunity to make friends in other countries without leaving home.
When
JOTA is held the third weekend in October of each year. JOTA takes place starting Saturday at 00.00 hours local time (12:00 AM) to Sunday, 24.00 hours local time (12:00 PM), though some activity continues over from Friday to Monday to take advantage of long distance (DX) time differences.