In what year was the Eurovision Song Contest organised for the first time?

Explanation

The Eurovision Song Contest was organised for the first time in 1956 in Lugano, Switzerland, mainly as a radio programme, and lasted 1 hour 40 minutes. 7 countries participated, including Switzerland, which won with the song 'Refrain', sung by Lys Assia. The competition was organised by the European Broadcasting Union (EBU).