The Polish number one was sent off in the host's opening game and subsequently only played 69 minutes of his country's campaign, with Poland crashing out in the group stages.
And after enjoying a strong breakthrough season at the Emirates Stadium, Szczesny admitted the events in Poland and Ukraine were tough to take, but he believes the whole experience will help him in the long term.
Szczesny told the club's official website: "It was obviously quite tough getting sent off in the first game and then being left out for the third match, but the experience of being there was different, something I have never had before.
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"Every time I play for the national team and hear the national anthem it is probably the best feeling a player can experience. But then the buzz [at Euro 2012] was unbelievable and if anything we wanted it too much.
"We were up for [the opening game], we had been preparing for four years and for me it all finished quite quickly. But to experience it will make not only myself, but the whole team, stronger."
And the 22-year-old is ready to accept his dismissal as simply another element of a steep learning curve, insisting the events in Poland and Ukraine have helped him to mature as a player.
"Obviously the sending off is [part of] a learning curve for me and hopefully that will never happen again. But it has made me more mature," Szczesny continued.
"Before the game I had never felt better in my life. Physically I was really fit and mentally strong and it just shows you that you never know what is around the corner. In that way it made me more mature."