Watch: Hundreds of young people queue at Spurs stadium for vaccines
Thousands stood in long queues for COVID vaccines on Saturday, as football grounds in London were turned into giant jab clinics.
But the crowds were also met by anti-vaxxers holding demonstrations outside.
Venues like Olympic Stadium, Stamford Bridge, Tottenham Hotspur FC, Charlton Athletic FC, Selhurst Park and Crystal Palace Athletics Centre were transformed into vaccine hubs during what has been dubbed 'Super Saturday'.
Smaller events are also taking place in local community venues in a drive to vaccinate as many Londoners as possible.
There were also pop-up clinics at universities across the country, such as in York and Canterbury.
It came as the NHS braced for a surge in demand after it announced that anyone over the age of 18 can now get a jab.
Mayor of London Sadiq Khan said he was "delighted" to visit Chelsea's ground at Stamford Bridge, which had 6,000 Pfizer vaccines to administer on Saturday.
COVID conspiracy theorist Piers Corbyn was among the protesters at West Ham's stadium.
He was pictured wearing a T-shirt with the slogan: "Resist, defy, do not comply".
Remeece, a rapper and the leader of anti-vax group Footsolderies4Freedom, was also seen at the venue urging people not to have the jab.
In Chelsea, Khan said: "You do not need to be registered with a GP to get vaccinated.
"It is great news that more than eight million doses of the life-saving COVID-19 vaccine have been given to Londoners, and now all adults over the age of 18 can get the jab.
"We are seeing the big difference that the vaccine is making in our fight against the virus, so I strongly urge all adult Londoners to book their appointments or attend a walk-in centre as soon as possible, and to ensure you get your second dose."
Vaccines minister Nadhim Zahawi tweeted: "This is an incredible effort by the whole London team. Happening across the City at Spurs, Arsenal, Charlton and West Ham too. Come on London let's get vaccinated!"
Meanwhile, it emerged that more than 721,469 jabs were booked on Friday when the vaccination programme was opened up to people aged 18 to 20.
This is the equivalent of more than 30,000 an hour or more than eight every second.
Watch: How many people booked a vaccine of first day jabs available to all adults
It comes as Public Health England said there had been a 79% rise in one week in cases of the Delta variant, first identified in India, with the increase being driven by younger age groups.
The bookings surge came at the end of a week that had already seen almost 1.8 million appointments made in just three days after the NHS vaccination programme opened up to people in their early twenties.
Some 692,299 appointments were made on Tuesday when 23 and 24-year-olds became eligible for a jab, with another 635,478 booked on Wednesday when the programme was extended to those aged 21 and 22.
There were another 456,366 appointments made on Thursday, meaning more than 2.5 million appointments were booked in just four days since bookings opened to under 25s on Tuesday.
NHS chief executive Sir Simon Stevens said: "This pandemic has been a challenge for everyone but the various restrictions have hit young people particularly hard.
"That's why it's good news that COVID vaccinations are now open to all adults across the country, and already well over three million people in their twenties have now had their first jab.
"So if you're 18 and over and haven't yet had yours, now's the time. It's the single easiest way to protect yourself, keep friends and family safe, and hopefully give us all our summer freedoms back.
"Please encourage your friends and loved ones to do the same, as we're now in the race to the finish line.
"The more of us who are vaccinated, the safer we all are, and the sooner freedom can return."
Health secretary Matt Hancock said: "It's incredible to see the enthusiasm young people are showing for vaccination across the country, and it is a testament to the fantastic work of the team in keeping as many people safe from COVID-19 as possible.
"If you've yet to book your appointment, I urge you not to hesitate in getting your jab and securing this protection for yourself and your loved ones."
Government data up to 18 June showed that of the 73,766,593 jabs given in the UK so far, 42,679,268 were first doses – a rise of 218,636 on the previous day.
Some 31,087,325 were second doses, an increase of 188,858.
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