Yesterday was Vietnam War Veterans Day. It’s the day the last troops were pulled from Vietnam.

In Washington D.C., near the intersection of 22nd Street NW and Constitution Avenue NW, just north of the Lincoln Memorial, stands their wall. A wall of black granite. It’s huge.

The Vietnam Veterans Memorial consists of 140 stone panels, polished to a high finish, sunken into the earth. The panels create a massive wall that is 493 feet and 6 inches long, about the size of a skyscraper laid on its side.

You expect the wall to be big, but you’re not prepared for how big it really is. This thing is ginormous.

I was in D.C. a few months ago. The granite gleamed in the morning sun, I stood before the never-ending wall of stone, sipping a bottle of water, taking it all in. The Washington Monument was on one side, Honest Abe was on my other.

There was an old man and his grandson roaming the wall, reading the names reverently. The old man had a wild white beard, he wore an army cap.

“Look, Grandpa,” said the kid, “is this one my uncle’s name?”

“Lower your voice,” said Granddaddy.

“But… Why are we whispering?

“Respect,” the old man said.

There was indeed a very respectful mood at the Vietnam memorial, which surprised me. I’ve been to U.S. war memorials before. And at most National Park Service war memorials the mood is nonchalant, happy even. Because most memorials commemorate wars that happened so long ago that nobody can remember them.

At the Gettysburg Memorial, for example, I saw hundreds of families pushing strollers, laughing, posing with performers in Civil War costumes, snapping selfies. At Arlington National Cemetery, I saw school kids playing tag among gravestones.

But people were silent here.

The Vietnam Veterans Memorial is not like other American memorials. Here, I saw old men touching the wall, heads bowed. There were people taking photos of names. There were families telling old stories. I saw a few people weeping.

There are 58,000 names of servicemen and servicewomen engraved on the wall. Names are chronologically ordered from 1959 to 1975.

Each name has a symbol next to it; either a diamond or a cross. The diamond means the death was confirmed. The cross means the soldier was either a prisoner or missing.

There are also 14 veterans who did not die whose names on the wall. This was due to clerical errors.

Eugene J. Toni was one such man. He lost part of both legs in Vietnam. He was in treatment for post-traumatic stress when his therapist recommended he visit the wall as part of his healing process.

One day Toni and his wife roamed the wall looking for the name of a relative who died in the war when he found his own name.

“It was kinda scary,” he said. “It was like seeing your name on a gravestone.”

Also on the wall are the names of women. There aren’t many, however. There are only eight women on the wall. All nurses.

“People forget about the nurses,” a woman at the wall nearby told me. “But if it weren’t for the nurses, this wall would be a lot bigger.”

Nurses like Second Lieutenant Elizabeth Anne Jones, who was killed before her wedding, along with her fiancé, they were in a helicopter crash near Saigon.

And Captain Mary Klinker, who was helping with Operation Babylift, evacuating hundreds of South Vietnamese children. She was on an overcrowded cargo plane filled with orphans when they all went down.

There were 265,000 women in the military during Vietnam. Nearly 11,000 of them served in Vietnam. Ninety percent were volunteer nurses.

I watched an old woman search the wall with a careful eye for nearly 15 minutes, roving the list of names. When she found the one she was looking for, she wiped her eyes. Then she placed paper against the wall and used charcoal to make a stone rubbing. She folded the paper, kissed it, and tucked it into her pocket.

I saw a man with a walker, wearing a leather vest adorned in military patches. He hobbled to the wall and stared at one name for a long time. I heard him say to his wife, “I was only 22 years old.”

I saw more than that. I saw people hugging. I heard noses blowing. I saw two white-haired women press their foreheads together and stay like that for a while. I saw a man light a candle and say a prayer.

Before I left, I passed the grandfather and grandson I’d seen earlier. They were standing before the inscription at the apex of the wall. The old man read the engraving aloud for his grandson:

OUR NATION HONORS THE COURAGE, SACRIFICE AND DEVOTION TO DUTY AND COUNTRY OF ITS VIETNAM VETERANS.

“What’s devotion, Grandpa?” said the boy.

The old man gestured to the wall and said, “You’re looking at it.”