Future of festivals hangs in the balance. ITV News Arts Editor Nina Nannar reports
The event is part of a series of trials (including the FA cup final, a nightclub, and a cinema) looking at how to get crowds back safely to mass events.
If deemed a success, it could be the foundation for how music festivals can go ahead safely this summer and going forward.
It comes as a similar try out in Barcelona last month, where the audience wore face masks, resulted in "no sign" of of higher levels of infection among those who took part.
Who are the lucky 5,000 who are going?
As it's a government-pilot event, tickets for Sefton Park weren't sold in the usual way.
They were, like most music festivals, hard to come by and only residents of the Liverpool City Region could buy one.
What are the rules?
The crowd will not have to social distance or wear face masks, but they will need proof of a negative Covid test before entry.
Ticket holders will take a lateral flow test at a local testing centre before entry - waiting the 30 minutes to get their results first. Attendees will then be asked to take another test after the event.
The gig-goers will also have to provide contact details for NHS Test and Trace to ensure everyone can be reached in the event of a positive test.
Organiser Melvin Benn, Managing Director of Festival Republic, says the aim is for the audience to "go for it as if coronavirus had never happened".
'We want them to behave without restrictions' says festival boss
"They'll be singing, they'll be dancing, they'll be having pints of beer, they'll be moshing, they'll be coming over the barrier," Mr Benn said.
Festival Republic is the promoter behind some of the UK's biggest events, including Latitude, Reading & Leeds Festivals, Download, and Wireless.
"We want them to behave without restriction in that sense so we can measure what the impact of the spread is," he said.
Musicians performing at the festival, like headline band Blossoms, have to undergo the same checks.
Tests, questionnaires, accreditation - what the musicians need to be allowed to perform
What will it tell us about the future of similar events this summer?
The overarching message from festival organisers so far has been they don't yet know what their events will look like in summer 2021.
Some have already cancelled, banking on 2022 being Covid-safe enough to go ahead as normal.
One of the major obstacles is the lack of pandemic-specific cancellation insurance in case scheduled events don't go ahead - it's an issue yet to be resolved.
Lack of Covid-specific insurance for festivals is 'the most significant hurdle'
"It's the most significant hurdle facing us," says organiser Mr Benn.
"We continue to talk to the government, I keep my fingers crossed," he added.
"I do believe at some point they will acknowledge that it's the only way to 100% allow the outdoor entertainment industry - not just festivals - to go ahead, at full capacity."
Other events sold out in minutes, with people desperate to party once more, but can provide scant detail about what Covid restrictions will be in place at festivals.
What events are going ahead this summer?
Taking a look at some of the biggest music festivals in the UK, here are some of the events that are going ahead and what they've said about Covid rules.
Creamfields - Organisers only mention face masks on their info page, stating government guidelines will be followed and banning offensive and full covering masks.
Latitude - The event will follow "all necessary safety protocols" but what they will be isn't yet known. The festival is expected to run at full capacity and attendees won't need to have been vaccinated but will need evidence of a negative test.
Boardmasters - The festival is planned to go ahead with no more information on Covid regulations.
Parklife - The event has pushed back from June to September 2021. Co-founder Sacha Lord told NME in February he was "extremely confident" the event will take place without any socially distancing regulations.
Isle of Wight - The festival has also been pushed back from June to September, with capacity reduced by 5,000.
Wireless - Organisers have also said vaccinations won't be mandatory but evidence of a negative test will be.
Kendall Calling - Again, a vaccination won't be mandatory but testing may be. Organisers said they would advice closer to the time.
Reading and Leeds - Both festivals are going ahead as planned. Mr Benn, who runs the events, has previously said certificates showing people are Covid-free could allow social distancing to be dropped.
What festivals have been cancelled?
The list of cancelled events over the Covid pandemic is very long. Here are some of the biggest name casualties for the 2021 festival season.
Glastonbury - Organisers cancelled the event for the second year in a row in 2021, "in spite of our efforts to move Heaven & Earth," they said. Tickets have been rolled over to 2022.
Download Festival - Organiser said despite their hard work the event is "not possible" adding they were "heartbroken" to cancel.
Boomtown - Perhaps the only festival to give explicit reasoning for cancelling, Boomtown said: "With less than four months to go until the event, and after almost half a year of collective campaigning to the government, sadly Covid specific cancellation insurance for events simply does not exist at this point in time."
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