Across Mexico, the US and Canada, inside a ribbon of land stretching 155 miles wide but more than 4,000 miles long, tens of millions of people craned their necks, tilted their heads to the sky and watched in wonder as the day turned to night.
What many saw on Monday was a phenomenon like no other: the Moon moving between the Earth and the Sun, extinguishing its light in a total solar eclipse.
The path of totality spanned the continent, beginning over the warm sands of a Mexican beach town and darkening the skies above the crashing waters of Niagara Falls before ending its journey on the shores of Canada's Newfoundland.
It left a sense of awe in its wake, a reminder of our planet's place in the universe.
The eclipse was first seen around Mazatlán, Mexico, on the country's western shores at 11:07 local time (18:07 GMT).
At first, the Moon's outer edge seemed to just be touching the Sun. Then it devoured more and more until cheers erupted as all finally went dark - save for the silvery glow of the "corona" effect of the Sun around the Moon's outline.
A thousand miles away in Dallas, Texas, 11-year-old Ady Walton-King was waiting, weeks of pent-up excitement ready to burst.
She had learned all about the eclipse in her fifth-grade class at Dallas Academy and on Monday morning she laced up her shoes and tucked four pairs of eclipse glasses into her pink purse - one for herself, one for each parent and one for her little sister, Abigail.
Just before it started, Ady sat down beside her dad, Ryan, on a school field in central Dallas and lifted her gaze upward.
And then it happened.
It all felt slow, she said, as she described the Texas afternoon turning dark. "It looked like the Moon was biting the Sun, but without the teeth marks."
Clouds slid in and out, occasionally blocking the eclipse from view until the Sun had vanished, nothing left but little flares of light around the Moon.
"I didn't think it would be like that," Ady said. "It was really dark out. I thought it would be like evening dark, but it was pretty close to pitch black."
The temperature dropped suddenly and, just as she had been taught, animals fell silent.
"As it started to get lighter the crickets were there, and the birds started singing. It was really crazy," she said. "I'm sad it's over."
From there, the eclipse moved on, carving its path north-east through the United States.
For some, the solar phenomenon was marked by a personal milestone, with hundreds of Americans joining one of several mass wedding events dotted across the path of totality.
In Russellville, Arkansas, 300 couples from across the country signed up, saying "I do" just before the sky went black. As the sky brightened, the group cut wedding cakes and danced - all part of the aptly named Total Eclipse of the Heart festival.
Following the Moon one state over, in Ellsinore, Missouri, was amateur astronomer Darcy Howard, who had driven from her home in central Arkansas to be sure bad weather didn't block her view.
She had seen many eclipses before today, two totals, one annular and two partials. "Each one has its own fingerprint," she said.
Totality today, at around 13:56 local time (18:56 GMT) brought an "eerie twilight", Ms Howard said, with dusky colours dotted all along the horizon. The corona was nearly as bright as a full moon. "The sense of other-worldliness was all around," she said.
The 70-year-old has loved the cosmos since her childhood, since her father showed her the Big Dipper, the North Star and the Milky Way, and bought her her first telescope.
"I was hooked," she said. "I can look through a telescope and see Jupiter… I can see Saturn. And when I see that in space, I know all is right with the world."
By 15:13 local time (20:13 GMT), the total eclipse had plunged the midwestern state of Ohio into darkness.
In Cleveland, where eclipse-watchers were graced by clear skies, the Sun's corona was clearly visible, a brilliant halo framing the Moon.
The stars came out in the middle of the day, a sight met with cheers and fireworks, a mid-April New Years Eve.
Many big American cities were not lucky enough to be on the path of totality - but the spectacles were still awe-inspiring. In New York, hundreds of people crowded on to the viewing platform of the Edge skyscraper in Manhattan to see what they could see.
They did not leave disappointed as the sun shrank to a crescent-like sliver of light that cast an unearthly pale gloom over the city.
Tourists had crowded along both sides of the border at Niagara Falls, where the eclipse path crossed from the US into Canada.
Here, the weather offered a formidable challenge, with thick grey clouds mostly obscuring the sky from view.
But just in time for totality - to the audible delight of the crowd - the clouds parted to reveal the black-hole Sun.
Nearby, on a Niagara City Cruise, 309 people celebrated by record-breaking - dressing up as the Sun to break the Guinness World Record for "Largest gathering of people dressed as the Sun".
The relentless motion of the heavenly bodies meant that the phenomenon did not last long, and it was Montreal that next got its chance to be plunged into temporary night.
In Montreal, 20,000 people crowded onto a field on McGill University's campus for an event held by the school's Trottier Space Institute.
"We had been expecting 8,000," programme administrator Caroina Cruz-Vinaccia said after. The weather was perfect, clear and bright skies. At the moment of totality, the crowd erupted at once, she said.
"I still can't quite find the words for how cool this was," she said. "We're still coming down."
Crowds were smaller on Newfoundland's Fogo Island, on Canada's east coast - one of the last places the totality could be viewed.
Bethany Downery, a Newfoundland native who works for the European Space Agency, tuned into the spectacular view from the Fogo Island Inn, nestled right against the Atlantic Ocean.
The skies were overcast, she said, but the clouds moved miraculously in time to catch near totality.
And with that, a day of collective wonder and celebration reached its conclusion. But it had left a permanent mark on many of those who had witnessed it.
In Dallas, a few thousand miles back along the path, Ady Walton-King was making plans.
Texas will not be in the path of totality again for another 300 years, so she'll have to travel for the next one in North America, in 2044.
And by that time, she'll be even more of an expert on total eclipses. "I want to be a scientist by the time that happens," she said.
