Submitted by Emerson Dameron:
In 1974, after 3 years of planning, a man named Oliver Bickar pulled off one of the world’s biggest (in size) April Fools’ Day pranks. He and his co-conspirators flew dozens of tires over to an extinct volcanic crater called Mount Edgecumbe on uninhabited Kruzof Island in Alaska. When he lit the tires on fire, people in Sitka, a town on the closest island, took serious note, wondering if the volcano, extinct for 4,000 years, had suddenly erupted. You can read the whole story on NowIKnow and at The Museum of Hoaxes.