16 year-old Thessa of Hamburg was looking forward to an unforgettable birthday party after inviting her friends via Facebook. Trouble is, she forgot to flag it “private”, and 15000 said they would attend. In the end only 1500 people turned up to be met by hundreds of police.

It all got a bit messy as the alcohol flowed, with neighbour’s gardens damaged and a number of fires started, and six arrests were made in front of the house in the quiet residential suburb, but Thessa did not see it – she had taken refuge at her Grandma’s house.