It’s not just hoaxes on the first day of the month that make April foolish in Chicago. Several major, memorable mishaps — one weather-related, one man-made and one Geraldo Rivera-hosted — celebrate anniversaries in April. 1906: In a 7,000-word story, the Tribune claimed “dinosauria” took over the city.

Google’s co-founders Larry Page and Sergey Brin launched a limited beta mail service, Gmail, on04. But, this launch was not taken seriously by their colleagues as the two had a reputation for pulling off some of the wildest jokes on April Fool’s Day.