Sporting Clube de Portugal vs. FK Partizan from Belgrade was the first ever match at the European Cup, what is known today as UEFA Champions League. And it took place... on September 4, 1955, exactly 70 years ago today. It ended 3-3.
Naturally, it was very different from what we know today, and in fact, it was born outside of UEFA, as an idea by French newspaper L'Équipe, named European Champion Clubs' Cup, with 16 teams participating, only one from each country (none English), and most of them invited as they were the respective winners of each of their domestic leagues, a true "Champions League", so to speak.
The first edition, in 1955-1956, was won by Real Madrid, who would went on to win the next four. Benfica won the new two, and AC Milan and Inter Milan won the next three. An English club did not win it until 1968, Manchester United: Scottish club Celtic won it the year before.
UEFA renamed the competition as Champions League in 1992, but many still remember it as the European Cup. Its prestige as the highest honour for a club in Europe remains, though, with Real Madrid still the leading club in the competition, having won 15 times.
Now, Champions League features 36 teams in its current form (debuted last year), although UEFA also hosts two other competitions, Europa League, and Conference League, with the same number of participants, to ensure a greater diversity in teams.