According to Official Guinness Records,
On 24 July 1999, a total of 34,309 people organized by Realizar Eventos Especias, gathered at the National Stadium of Jamor, Lisbon, Portugal, to create the Portuguese logo for Euro2004, as part of the successful Portuguese bid to UEFA to hold the European football championships in 2004 The kicking leg of the player in the logo was composed of 651 gymnasts wearing black and white capes, which when swapped over, created the illusion of the player kicking the ball. Once the ball was kicked, it released 10,000 red and green helium balloons - the colours of the Portuguese flag. As part of the bid, the crowd shouted 'Portugal we love football' and sang the national anthem.
For a complete list of 1999 records, please visit 1999 Guinness Records in Portugal.