Project X Haren was an event that started out as a public invitation to a birthday party by a girl on Facebook, but ended up as a gathering of thousands of youths causing riots on 21 September 2012 in the town of Haren, Groningen, Netherlands. The event was unprecedented in the Netherlands, but in June 2011, a German girl posted similar birthday invitations on the internet. Hundreds of mostly drunk youths gathered in Hamburg, Germany, causing a great deal of damage and rioting against the police.