After weeks of anticipation, onlookers experienced an astronomical phenomenon - two minutes in which the moon moved directly in front of the sun to create near darkness and cause a precipitous drop in temperature. The eclipse drew whoops and cheers from onlookers in Depoe Bay, Oregon, near where "totality" - the shadow created by the sun's disappearance - started.
"It just kind of tickled you all over - it was wonderful - and I wish I could do it again," said Stormy Shreves, 57, a fish gutter who lives in Depoe Bay. "But I won't see something like that ever again, so I'm really glad I took the day off work so I could experience it."
The last time such a spectacle unfolded from one U.S. coast to the other was in 1918. The last total eclipse seen anywhere in the United States took place in 1979.
The rare cosmic event was expected to draw one of the largest audiences in human history, including those watching through broadcast and social media.
Some 12 million people live in the 70-mile-wide (113-km-wide), 2,500-mile-long (4,000-km-long) zone where the total eclipse was to appear, while hordes of others traveled to spots along the route.
"It was incredible," said Cheryl Laroche, 57, who with her husband, Rob, joined other observers at Roshambo ArtFarm in Sheridan, Oregon. "It was literally cold and dark. The light was blue."
The eclipse first reached totality in Oregon at 10:15 a.m. PDT (1715 GMT) and began marching slowly eastward across the country. The phenomenon will take its final bow at 2:49 p.m. EDT (1849 GMT) near Charleston, South Carolina, where eclipse gazers gathered atop the harbor's sea wall.
Nancy Conway, 57, an elementary school principal, said she and her family made the drive to Charleston from Lynn, Massachusetts.
"Twenty hours, three drivers, four adults, two 6-year-old twins," Conway said as she sat in a lawn chair facing the harbor. "It's a once-in-a-lifetime experience."
A number of towns within the total eclipse's path set up viewing parties. At the Southern Illinois University campus in Carbondale, Illinois, the 15,000-seat football stadium was sold out for Monday.
"I woke up at 4 a.m. so I'm excited," said Madeline Rubin, 17, who drove two hours to the stadium with others wearing T-shirts that said "I totally blacked out."
For millions of others outside the zone of totality, a partial eclipse will appear throughout North America, a spectacle that attracted its own crowds.
In Washington, D.C., hundreds of people waited in long lines outside the National Air and Space Museum, which was distributing more than 20,000 pairs of free viewing glasses. Residents of the nation's capital will see 81 percent of the sun obscured at the eclipse's peak around 2:24 p.m.
Perhaps never before have so many people had the opportunity to see a total eclipse, said cartographer Michael Zeiler, who maintains the www.greatamericaneclipse.com website and is a self-described "eclipse chaser" who on Monday will mark his ninth time seeing "totality."
Zeiler estimated up to 7.4 million people traveled to the zone to observe the total eclipse, which is taking place in the peak vacation month of August.
Many people trekked to remote national forests and parks of Oregon, Idaho and Wyoming. Those who live along the path, which cuts through a few population centers like Kansas City, Missouri, and Nashville, Tennessee, were able to simply walk out their homes and look up.
For those outside the shadow's path or trapped indoors, a NASA-linked website, eclipse.stream.live, and a companion mobile app provided a live stream filmed from the vantage point of 50 helium-filled balloons at a height of 80,000 feet (24,384 meters).
During a total eclipse, the sun's disappearing act is just part of the show. The heavens dim to a quasi-twilight and some stars and planets become visible.
The last glimmer of light gives way to a momentary sparkle known as the "diamond ring" effect just before the sun slips completely behind the moon, leaving only the aura of its outer atmosphere, or corona, visible.
The corona marks the peak phase of totality and the only stage of the eclipse safe to view with the naked eye.
Thumbnail Credit: REUTERS, Rick Wilking