On Saturday, January 21, 500,000 people gathered on the Washington Mall. Hundreds of thousands more met in New York City. And in Chicago. And Denver. And Los Angeles. And Helena, Montana; Lexington, Kentucky; and Fairbanks, Alaska, where more than 3,000 brave humans, bundled in coats and heavy gloves, gathered in temperatures that hit 20 degrees below zero. All these people — in state capitals and small towns and on the National Mall and on a research ship in Antarctica — were there for the Women's March.

Their signs — ranging from the size of an envelope to nearly 6 feet tall; some made by small children ("EVERYONE IN THIS CITY IS NICE") and some depicting Vladimir Putin using Donald Trump as a marionette — told the story of the 2016 presidential campaign from the perspective of those who lost: one in which a former reality show star shattered behavioral norms and won the presidency on the backs of refugees and minorities and immigrants and women. The posters were covered in glitter and paint, or drawn in Sharpie. They said things like: "THIS PUSSY GRABS BACK," "MY BODY MY CHOICE," "DIVERSITY IS BEAUTIFUL," and "I CAN'T BELIEVE I STILL HAVE TO PROTEST THIS SHIT."

In Washington, most of the people who gathered for the march were women. Young women, middle-aged women, women who had flown in from across the country and stayed on friends' couches in the D.C. suburbs, elderly women who screamed "SHAME, SHAME!" when they passed the Trump International Hotel on Pennsylvania Avenue. I came with my other half, walking from our apartment to the ivory-colored Capitol Building that marks the end of the Mall where the march began. I didn't carry a sign, because "THIS ALL SEEMS STRANGE AND I DON'T LIKE IT BUT I WOULD LIKE TO UNDERSTAND IT AND PERHAPS WITH ADEQUATE RESEARCH I CAN ARRIVE AT SOME SORT OF CONCLUSION REGARDING THE EVENTS AT HAND THAT WILL HELP ME COME TO TERMS WITH IT" didn't quite fit.

The march was scheduled to begin at 1:15 p.m.; by noon the Mall was already completely packed with people and signs and pink hats and the occasional small dog. One woman walking behind us stopped and stared at the Capitol Building, roughly a city block away and still covered in American flags from the inauguration. "It looks just like how I thought it would!" she said, her voice high-pitched with excitement. "It looks just like how it does on TV!"

There were men there, too, thousands of them, carrying signs that read things like "MEN OF QUALITY DON'T FEAR EQUALITY" and "WE SHOULD ALL BE FEMINISTS." There were children on the shoulders of their parents, and older people in wheelchairs being carefully navigated across the white protective panels that cover the grass of the Mall to keep it safe until spring. I ran into a former college classmate and then one of my old roommates, seeing both for the first time in years. It felt as if everyone I knew, every college friend and old co-worker and former boss, was out there, under a steel-gray sky on a January afternoon.

So many people came that rivers of human beings streamed into nearly every street of downtown D.C. There were so many people, in fact, that the Women's March nearly became the Women's Stand in One Place; police told organizers that the expected 200,000 attendees had become an estimated half a million, overcrowding the entire route, which had been intended to wind from the steps of the Capitol Building to the front door of the White House. "Essentially, as soon as they turned around, the march would be over,” one city official told The Washington Post. There were speakers on a stage somewhere, we were told, but none of us could hear them; all we heard was whoever was standing next to us as they tried and failed to call their friends (every cell phone network seemed to die in unison), as well as sporadic chants of "LET US MARCH!"

But then, almost as if we'd all received some sort of telepathic go-ahead after hours of standing in the middle of the Mall in 45-degree weather and occasionally cheering, we moved — in one noisy but polite mass of humanity, guided by police officers who seemed much friendlier than usual. "Can we cross this police tape?" an older woman next to us asked a D.C. cop. "If you do, I won't say anything," he replied. Perhaps the police were kinder and gentler to us because many of the people on the Mall were white women, wearing cat-ear hats and walking next to their daughters, friends, and cousins. Perhaps they were kinder and gentler to us because in D.C., Hillary Clinton won the 2016 presidential election by a landslide, and D.C. cops vote, too.

And then, nearly an hour after the march had been scheduled to start, it escaped from the Mall. It felt like every square inch of available concrete was full of pink-clad marchers, with protesters high-fiving drivers while weaving around cars that wouldn't be able to move for hours. We walked down Pennsylvania Avenue to the White House, and many of those marching turned around to look back at the thousands and thousands still coming, still walking, still working their way toward Trump's new home. We kept asking people in the crowd, "Is this the most people you've ever seen?" The answer was always, "Yes!"

A lot of those I passed on the march were furious — about the election, and about discovering what a lot of people already knew: that many of their fellow Americans hate them. When an SUV pulling a Trump-supporting float emblazoned with American flags and signs blaring "Secure Our Borders," and "TRUMPUNITYBRIDGE.COM" tried to pull out into traffic in the middle of the march route, it took a police escort to keep the booing crowd out of the way. Maybe the float had been trying to stop the march. Maybe they were just trying to get out of town. No one knew, not even the officers tasked with protecting them. A teenage boy in the SUV held a pride flag and tried to give the crowd a peace sign, looking more confused than upset.

But the marchers were also invigorated, almost euphoric, because after realizing that much of the country doesn't see the world the same way they do, they were finally surrounded by people who were just as upset and just as willing to take action. Eating dinner later at a neighborhood pub surrounded by marchers just as exhausted as we were, a woman at the table next to us told me that this was the first time she'd felt normal since the night of the election. "I just feel better knowing that a lot of other people are angry, too," she said. Of course, not everyone was angry; many were primarily scared. One man behind us on the street held a sign reading, "CONGRATULATIONS, MR. PRESIDENT. NOW LEAD WITH INTEGRITY AND RESPECT." In his other hand, he held another that read "NOT A SORE LOSER! WORRIED!"

I ran into another man carrying a sign outside the Women's Equality National Monument, a memorial near the Supreme Court, that said "MIDTERM PAYBACK 4 REAL." "That's what we gotta stay focused on," he told me. "We gotta get these guys outta Congress, and then the president won't be able to DO this shit." He was right. Because for all of the people and the posters and the chants and the crowds we saw on Saturday, from D.C. to Berlin and almost everywhere in between, it won't matter unless we make it matter.

For many, this march was an emotional release, but it must also be a political launch point. None of it will mean anything — not a single clever sign or forceful chant or cute pink hat — if in 652 days, every single person who marched in the cold and the rain and, in some places, the snow to stand up to Trump and his agenda don't show up to vote in the 2018 midterm elections that could reshape the House and Senate.

We walked together, thousands of us, united by anger and fear and concern about ourselves and our loved ones and our country. But then we all went home, back to apartments and mortgages and jobs and lives now taking place in an America where Donald Trump is still president. It's going to take a new kind of unity, a kind that circumvents the differences between us that are the reasons we don't usually join together in giant marches or small groups or, hell, even Sunday brunches, to handle it.

As I looked out over the sea of people on Saturday, I thought, I wonder what all these people could do if they really tried. I hope I get to find out the answer.