By Steve Large

SACRAMENTO (CBS13) — International travelers are descending in downtown Sacramento this week for the single-biggest annual event the city hosts.

The Aftershock Festival is back after a COVID cancellation in 2020.

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Around 40,000 people are expected each day over the course of the four-day event starting Thursday.

The transformation has started and the stage is being set for the crowds at Sacramento’s Discovery Park—a temporary city within a city.

The outdoor venue will have lots of COVID protocols in place.

“From the beginning of the year, as long as we were going to be allowed by the local authorities, we were going to be bringing this event back and we were going to be doing it safely,” Danny Wimmer Presents Chief Marketing Officer Chamie McCurry said.

The Aftershock Festival is so popular, people are arriving to see the musical performances from every state in the country, and more than a dozen countries around the world.

“So we get a ticket report on who’s bought tickets, what their zip code is, or what country they come from,” Visit Sacramento CEO Mike Testa said.

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Preventing a COVID superspreader event is top of mind for all involved.

“I think it’s always a concern until COVID is behind us but I look at the examples of Lollapalooza in Chicago. I think they had 200,000 people and four tested postive after the fact,” Testa said.

Sacramento County Public Health issued a statement saying they provided Aftershock’s organizers “information regarding the current California Department of Public Health guidance for mega-events which include requiring proof of vaccination or a negative COVID test.”

Patrick Miller is the general manager of the Hyatt Regency in Sacramento. It’s sold out this weekend because of Aftershock.

“Pretty amazing to say, especially in this new world, to be able to fill all those up,” Miller said. “We had it marked on the calendar, and we’re ready for it.”

Rock ‘n roll and COVID protocols, Aftershock is making Sacramento an international destination again.

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The Aftershock website also posts a page reading attendees assume all risk related to exposure to covid and agree to waive all claims against the city, county, Discovery Park and Danny Wimmer Presents.