WASHINGTON - Metro officials say 558,735 people rode Metrorail on Saturday, as hundreds of thousands of people walked through the streets of the District for the March for Our Lives demonstration, carrying signs and chanting "Never Again" and "We Want Change."
At 4 p.m. Saturday, WMATA reported Metrorail ridership was at about 334,000 for the day, which they said was about 2.5 times the amount for a normal Saturday.
The Archives Metro Station was shut down for some time due to high volume, with Yellow and Green Lines bypassing the station.
Many activists found other ways to get into D.C. and arrived via buses, ride-sharing services and by carpooling.
While march organizers projected over 500,000 would be in attendance for the event, they later reported on social media that over 850,000 people were in D.C. for the march.
The National Parks Service says it no longer reports crowd estimates and hasn't done so since the Million Man March in 1995.
However, CBS News reports that over 200,000 people attended the march in the District Saturday, according to Virginia-based firm Digital Design & Imaging Service Inc (DDIS). The company uses a proprietary method for calculating crowd size using aerial photos.
According to DDIS, the peak crowd size was 202,796 people, with a margin of error of 15 percent, the firm said. The crowd reached its largest size at 1 p.m., according to the company's estimates.
The New York Times reported crowd scientists estimated that at the January 2017 Women's March on Washington, there were at least 470,000 people. DDIS estimated the number for the Women's March at 440,000 people.
Metro reported that ridership for the day of the Women's March reached over 1 million, which was Metro's second-busiest day in history, behind President Obama's 2009 inauguration.
The march, organized by student survivors of the Feb. 14 school shooting in Parkland, Florida, brought throngs of people, especially students, to the Nation's Capitol in hopes of sending a message to lawmakers for stronger gun control laws and shine a light on the NRA's financial control of several members of Congress.
Several superstar celebrities took the stage to perform during the event, including Jennifer Hudson, Ariana Grande, Demi Lovato, Common, Vic Mensa, Andra Day, Miley Cyrus, Lin Manuel Miranda and Ben Platt.
More than 800 sister marches took place across the U.S. and globe. Organizers said they had expected more than 1 million to collectively participate in the protests.
While hundreds of students from Marjory Stoneman Douglas High School were in the District for the March For Our Lives, many students from the school remained in Parkland, Florida for a sister march there. More than 20,000 demonstrators participated in the rally in Parkland.
The demonstration in D.C. featured several powerful speeches from students across the nation. One of those students, 11-year-old Naomi Wadler of Alexandria, Virginia, electrified the crowd as she denounced gun violence.
"I am here to acknowledge the African-American girls whose stories don't make the front page of every national newspaper," said Naomi as the crowd roared. "These stories don't lead on the evening news. I represent the African-American women who are victims of gun violence, who are simply statistics instead of vibrant beautiful girls full of potential."
"My grandfather had a dream that his four little children will not be judged by the color of their skin, but by the content of their character," said Yolanda Renee King. "I have a dream that enough is enough and that this should be a gun-free world. Period!"
Historians said the demonstrations, including a national school walkout held by the organizers on March 14, were shaping up to be one of the largest youth protests in decades. The student protesters have dismissed criticisms that they don't have the credentials to change laws, noting that, historically, many political movements have been sparked by youth.