That song would most likely be Waterloo by ABBA, Sweden’s famous 1974 entry.

Compilation contests have been held throughout the years, the most famous one being the Congratulations: 50 Years of Eurovision. Waterloo was chosen to be the best of the bunch by online voters and juries from each of the participating countries. Recently, the BBC did a polling, and Waterloo won again. The song appears high on the lists of many Eurovision fans, and is often considered to be the most iconic Eurovision song ever, since ABBA reached world fame relatively shortly after they won Eurovision, producing hits like Dancing Queen, S.O.S., Chiquitita and Mamma Mia. Even today, Waterloo is one of the most streamed Eurovision entries ever.

Waterloo is frequently challenged by a modern compatriot: Euphoria by Loreen. The sophisticated lyrics, ahead-of-its-time composition and immersive staging took Europe by storm and sent Sweden to instant Eurovision domination. It changed the image of Eurovision, which was at the time seen by the vast majority of countries as a cheesy, politically biased sh*t show. Many recent Eurovision participants called it their all-time favourite Eurovision song, and it sure influenced quite a few entries. Ever since its participation in 2012, Euphoria has dominated the ESCRadio Top 250 and it has been a mainstay at Eurovision and non-Eurovision parties. As more and more countries start seeing Eurovision as a springboard for musical acts, we can expect more big hits in the future. The two most streamed Eurovision songs of all time are from 2019, the most recent edition.