It's also going to be impossible to gauge how many people exactly attended Trump's inauguration as opposed to the Women's March Saturday organized as a direct rebuttal to Trump the previous day.
But there's going to be a lot of conjecture about it. Trump himself talked about his massive crowds during an appearance at the Armed Services Ball Friday night.
It's clear that both events attracted many people. Below are pictures from 12:15 p.m. ET on each day from the EarthCam
Trump talked about crowd size during an appearance at the CIA Saturday and argued the size of his crowds had been misrepresented.
"We had a massive field of people," he told the US intelligence agency. "You saw that. Packed. I get up this morning, I turn on one of the networks, and they show an empty field. I'm like, wait a minute. I made a speech. I looked out, the field was, it looked like a million, million and a half people. They showed a field where there were practically nobody standing there. And they said, Donald Trump did not draw well," the President said.
"It looked honestly like a million and a half people, whatever it was, it was, but it went all the way back to the Washington Monument and I turn on, by mistake, I get this network, and it showed an empty field. Said we drew 250,000 people. Now, that's not bad. But it's a lie. We had 250,000 people," he said.
It wasn't clear which outlet Trump was referring to. CNN has not reported a specific size to the crowd since there has been no official estimate.
Trump took the oath of office just before noon Friday and then gave his inaugural address. A rally associated with the march was slated for between 10 a.m. and 1 p.m. on Saturday.
Some differences to note: Trump's speech was on the West Front of the Capitol, which was at capacity on Friday. It was cordoned off and empty on Saturday as protesters gathered on the Mall.
On the other hand, the Women's March filled the streets around the mall. Those streets were closed to Trump supporters.
His inauguration was on Jan. 20, because of the Constitution, which this year occurred on a Friday. The Women's March was on Saturday, when more people are off work.
Metro, Washington's subway system, tweeted Saturday there were 275,000 trips taken Saturday by 11 a.m.
On Friday, there were 193,000 trips by 11 a.m., according to Metro.
Another important point: Both events are occurring in an area opposed to Trump. Washington, D.C. voted overwhelmingly against Trump last November. He got just 4.1% of the vote in the nation's capital
. He also lost the surrounding states of Maryland
by 25 percentage points and Virginia
by nearly 5 percentage points. It would be a longer trip for a critical mass of Trump supporters than for a critical mass of marchers.
It should also be noted that marchers took to the streets in other cities, nationwide, and in cities around the world.
"Sister marches" also took place in Chicago:
And New York:
And in Boston:
Here are some of the best pictures from American cities:
And images from other countries, too: