In Colorado this weekend, hundreds of high school seniors turned their tassels and graduated — one of them had just been waiting for it longer than the others. Forty-two years longer, to be exact. Dennis Collins, now 60, walked across the stage on Saturday and collected the diploma that he'd sacrificed by heading off to Vietnam in 1966.

Collins says of his decision to go, “Vietnam was becoming a big issue. It was just kind of what you did. I was raised to believe you served your country and whenever you got out, you served your community.” He continues, “In Vietnam, you didn’t like it or not like it. It was something you did because it was something your country said to do. … It was my duty to do it, and I did it.” To see how Collins was able to graduate and more scenes from this Memorial Day, read more.

The program that allowed Collins to get his diploma is called Operation Recognition. It was enacted in 2003 and authorizes veterans from World War II, Korea, and Vietnam to receive their high school diplomas. The program recognizes the “sacrifice and contribution of those who honorably served our country."

Collins graduating class was delighted to have him. “They all applauded. I didn’t ask them to do that. They had an excitement all of their own. … It was exciting to me the students showed that enthusiasm. I think it did mean something to them.” said their high school principal. Collins was thankful to everyone who made his graduation possible. He said, "Most of all, I want to thank the kids for taking on an old fart like me. They’re making an old man’s dream come true.”

Colorado remembered Dennis Collins service — here are some more scenes of remembrance from around the country this Memorial Day.