Professionally filmed video footage of METALLICA performing the song "Frantic" on October 8 at the Aftershock festival in Sacramento, California can be seen below.
Around 40,000 people attended each day over the course of the four-day event starting on October 7 at Sacramento's Discovery Park.
A number of COVID protocols were in place for this year's Aftershock, with Sacramento County Public Health issuing a statement saying they provided the festival 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."
Chamie McCurry, chief marketing officer with production company Danny Wimmer Presents, said: "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."
McCurry said that METALLICA was the biggest draw this year, performing two nights of the festival.
"It's a truly unique experience for METALLICA fans to be able to see them two nights, never repeat a song. Two completely different sets," McCurry told KCRA. "This is something that's part of history."
Mike Testa, president and CEO of Visit Sacramento, said that this year's Aftershock was expected to generate an economic impact of close to $30 million.
In August, Danny Wimmer Presents announced that the sold-out Aftershock would require attendees, staff, crew and artists to provide proof they have been vaccinated against COVID-19 or a negative test within 72 hours of their first day at the festival. The festival also added a section to its web site about virus safety guidelines.
In a statement posted on social media, Danny Wimmer Presents founder Danny Wimmer said: "We are at an unprecedented crossroads with uncertainty about whether or not our festivals will happen this Fall. It is not my nature to idly sit back and let others decide our fate. Instead, I am going to do everything in my power to ensure that our festivals happen, even if that means enacting policies that some people may not agree with. But before you react negatively to our policy, please consider this. What I see is that the fans feel the world needs music festivals now more than ever. We need to bring people back together to heal from the past 18 months. We need to get the people and artists whose livelihoods depend on live events back to work. I am confident that these requirements are what is needed to guarantee that we have fun and safe festivals this Fall."