Four hours north of Atlanta in Nashville, Tenn., the largest U.S. city in the path of the solar eclipse’s totality Monday, Aug. 21, the Adventure Science Center is hosting a weekend of free outdoor events to celebrate.

Food trucks, music and a science tech festival will be on the lawn. Speakers will appear Saturday and Sunday before the official viewing event Monday.

Events inside the center, for which there is a charge, include the Sudekum Planetarium show “Eclipse: The Sun Revealed,” on which production began a year and a half ago.

Derrick Rohl, the planetarium manager, said the Great American Eclipse is one of the biggest celestial incidents of his lifetime.

“If you’re inside the path, you can look up and see the sun’s atmosphere,” Rohl said. “People say it looks like a hole got punched in the sky. The sun and moon look like they’re the same size.”

In ancient times, before people knew what was happening, Rohl said, a solar eclipse caused terror because it disrupted the basic pattern of life.

“Every single day, the sun comes up in the morning and goes down at night,” he said, but an eclipse breaks “the concept of day and night.”

Heather Middleton, the vice president of public relations at the Nashville Convention and Visitors Corp. visitors center, said the city expects 50,000 to 75,000 visitors, most of them staying overnight.

The Upper Cumberland Regional Airport plans a fly-in for pilots who want to view the eclipse with their families. The airport in Sparta, Tenn., created the event after receiving calls because of its location within the path of totality, said Dean Selby, the airport manager.

“We’re right on the center line within the path of totality,” he said. “We started receiving calls about a year ago from people who wanted to come here and view it, so we decided to host a ticketed event.”

Selby said a structured event is better and safer than a free-for-all.

The airport is charging $25 per ticket. A month before the eclipse, Selby had 27 reservations, with families flying single-engine planes from as far away as California. He expects more pilots to sign up as Aug. 21 gets closer.

“We receive about four to five calls a day,” Selby said. “We can take 120 reservations comfortably, but I don’t know how bad it’s going to get.”

On the post-Georgia side of the eclipse’s path, SolarEclipseFest at Chattooga Belle Farm in Long Creek, S.C., is sold out, said Kitty Land, co-owner of the farm and its distillery. She bought 2,500 cups a year ago and began selling tickets for the festival in April.

“I think we should have some people coming the day of,” said Land, who is reserving some tickets in case ticketholders want to bring additional friends and family.

The 238-acre farm is in the path of totality, and Land has planned a full weekend with food trucks, speakers, a drum circle, musical performances and an art show. People are coming to the festival from all over the world, she said.

“It will never happen again in our lifetime,” Land said.

More eclipse events and information for neighboring states can be found at www.eclipse2017.org.