On August 21, a total solar eclipse will swing across the United States in an arc from South Carolina to Oregon. Total solar eclipses are rare—the last one visible in the lower 48 took place in 1979 and the next won’t be until 2024.

You’ll want to catch this one. People report that seeing an eclipse is an eerie and emotional experience—and they frequently struggle to find words that describe what it feels like when the moon entirely blocks out the sun for those two fleeting minutes. There will be stars in the sky and the sun’s chaotic, exploding atmosphere peeks out around the edges of the moon. Birds stop singing, believing that it is suddenly night, and the shadow of the moon races across the landscape at 1,800 miles per hour. But articulating that sensation is a different story.

Writer Annie Dillard witnessed that 1979 eclipse from a hilltop in Yakima, Washington. In her essay "Total Eclipse," from the book Teaching a Stone to Talk, she says that people (including herself) screamed involuntarily when they saw the shadow “hauling darkness like plague behind it. Seeing it, and knowing it was coming straight for you, was like feeling a slug of anesthetic shoot up your arm.”

Mesmerized by descriptions like Dillard’s, thousands of people spend their vacations chasing total solar eclipses around the globe (one occurs somewhere on Earth every 18 months on average), and even charter jets to watch them over the Arctic.

Here is the catch: You need to be within the 70 miles of the moon’s direct shadow, the umbra, or you won’t see the eclipse at all. The naked eye won’t detect a difference in a sun that is even as much as 85 percent obscured, for example. According to Dillard, seeing a partial eclipse “bears the same relation to seeing a total eclipse as kissing a man does to marrying him, or as flying in an airplane does to falling out of an airplane.” So you’ll want to join the thousands of “umbraphiles,” along the eclipse’s narrow, coast-to-coast pathway on August 21.

The most tantalizing spot on that pathway is Jackson Hole, Wyoming. Viewing an eclipse at the foot of Grand Teton National Park would be a spectacular sight. However, Jackson is expecting an absolute swarm of people for the eclipse—perhaps as many as 80,000 visitors will squeeze into a narrow valley that usually accommodates only 23,000. Grand Teton National Park expects its all-time busiest day on August 21, and most hotel rooms have been booked for a year. What’s more, the valley has precious few roads, so even if you do find lodging, you may end up seeing the eclipse not from a lofty mountaintop, but from a gridlocked two-lane highway.

Instead, check out eastern Idaho, just over Teton Pass. Idaho Falls is a small city in the middle of wide-open potato fields and is only a 3.5-hour drive from Salt Lake City. It’s within the “path of the totality,” and the Museum of Eastern Idaho is one of NASA’s Official Viewing Locations.

“We are rolling out the red carpet for eclipse viewers,” says Kerry Hammon, Idaho Falls mayor’s office spokesperson. The city has designated four city parks as viewing areas and opened three others for overnight camping. In addition, she says, the city revised its ordinances to allow Airbnb rentals, which weren’t legal prior to 2017. She notes, “The eclipse definitely accelerated that change.”

Nearby towns like Rexburg, just 30 miles north, and Pocatello, which is 52 miles south, offer alternate accommodation as well. In either case, Hammon recommends travelers print out directions to lodging or viewing sites ahead of time, as the city expects the influx of visitors to clog or even crash the cellular networks. “Don’t expect to be able to Google directions,” she says.

The Museum of Eastern Idaho will host NASA speakers all weekend long, and on the actual day, NASA will live broadcast the eclipse from the Museum to NASA TV as well as local and national news outlets. Dr. James Green will provide a scientific play-by-play. The eclipse starts at 10:15 a.m. and the totality begins at exactly 11:33:04 a.m. It will last for exactly 1 minute and 41 seconds.

Another good viewing spot is Melaluca Field ballpark, home of Idaho Falls’ minor league team, the Chukars. Up to 10,000 people will fill the stands and field to watch the eclipse and hear presentations from a panel of astronomers and an astronaut.

If you have to have the Tetons in your eclipse, head to the towns of Victor and Driggs, on the Idaho side of the mountains. Both are Teton-adjacent and closer to the centerline of the umbra than Idaho Falls and will, therefore, have longer totalities. Driggs, for example, will have a totality of 2 minutes and 18 seconds. Climb a Teton to get a better view, but don’t expect to rely on the chairlift rides at the nearby Grand Targhee ski resort—they’re already sold out.

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