Hosts France became the first team to qualify for the knockout stages after late goals from Antoine Griezmann and Dimitri Payat crushed brave Albanian resistance in Marseille.
Marek Hamsik produced the best individual performance of the tournament so far to lead Slovakia to a 2-1 victory over Russia in Lille.
Unfancied Hungary pulled off one of the surprises of the tournament so far when they beat 10-man Austria 2-0 in Bordeaux.
Italy won the first clash of tournament heavyweights, beating Belgium in Lyon thanks to Emanuele Giaccherini's first-half goal and a late Graziano Pelle strike.
Republic of Ireland and Sweden shared the spoils at Stade de France in a match that neither could afford to lose.
Germany opened with a win in Lille but were far from convincing in defence.
Luka Modric's clever volley was enough to secure victory for Croatia over Turkey in their tournament opener in Paris.
Wales kick off their Euro 2016 campaign with a 2-1 win over Slovakia.
Switzerland pushed all the way by ten-man Albania.
Dmitri Payet scored a dramatic late winner as hosts France edged the opening match of Euro 2016