The world's largest critical care unit and the first of the UK government’s emergency field hospitals to treat coronavirus patients has opened in east London's ExCel centre.
The ExCel exhibition space - usually used for large events such as Crufts and Comic Con - was transformed into a hospital in just 10 days.
The temporary NHS Nightingale Hospital is able to hold up to 4,000 patients and will be staffed by NHS medics with help from the military.
Prince Charles paid tribute to staff as he officially opened the hospital via video link from his home on the royal Balmoral estate in Scotland.
The Prince of Wales, who was recently diagnosed with Covid-19 and spent seven days in isolation called it "a spectacular and almost unbelievable feat of work".
He said it showed how the impossible could be made possible and how we can achieve the unthinkable through human will and ingenuity.
He added: "In this dark time, this place will be a shining light."
Also at the ceremony was Health Secretary Matt Hancock - who has just come out of quarantine after having the virus.
He praised the NHS and the way its staff are dealing with the pandemic.
Hancock said: “In these troubled times with this invisible killer stalking the whole world, the fact that in this country we have the NHS is even more valuable than before.”
He added: “It is the best of efforts. It is the best of the NHS.It is the best of Britain to come together in these difficult circumstances to put together such a facility, at such pace, that will be there for people so that we can give the very best care. And so that as a nation we can come through this crisis in the best way we possibly can.
Other hospitals to be opened across the country
More Nightingale hospitals are planned to open across the UK, including in Cardiff, Glasgow, Manchester, Harrogate and Bristol.
The new sites, in Bristol and Harrogate, will provide up to 1,500 extra beds for patients with Covid-19.
New cases this week
According to the latest figures, 2,921 people in the UK have died with the virus. The total is up by 569 from 2,352 the day before, which was the biggest day-on-day increase so far.
Earlier, Mr Hancock said the government had "a huge amount of work to do" to meet its target of 100,000 tests a day in England by the end of April amid controversy over the roll-out of testing for coronavirus in the UK.
"It's got to happen. I've got a plan to get us there, I've set it as a goal and it's what the nation needs," he said.
The 100,000 could include both swab tests, that check if someone has the virus, and antibody blood tests, to check if someone has had the virus recently - but which have not yet come into widespread use.