This image shows a coronavirus doctor waiting for the first patients to arrive at the new NHS nightingale hospital.
Professor Richard Schilling is Deputy Clinical Director at the COVID-19 hospital in east London.
He tweeted the image of him waiting at an entrance before the hospital started receiving its first patients yesterday.
The cardiology specialist said: "I find this photo of me waiting for our first patient both sad and moving.
"I wish we didn’t have to be here."
Professor Schilling is one of thousands who have volunteered to work at the specialist coronavirus hospital build in London's enormous ExCel conference centre.
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Similar hospitals are in the pipeline across the UK, including in Cardiff, Glasgow, Manchester, Harrogate and Bristol.
A spokesperson for the NHS Nightingale said: "Our first patients have now been admitted to the NHS Nightingale London, as planned.
"There is also treatment capacity available in other hospitals across London to complement the care being provided at the London Nightingale."
The NHS Nightingale confirmed on social media it was now operational and thanked other emergency services for their assistance in transporting patients.
It wrote on Twitter : "This evening the @RoyalAirForce and @Ldn_Ambulance practiced a patient transfer. Speed and efficiency come naturally to our emergency responders #ThankYou for helping us to treat the people that need us, when they need us most."
Professor Richard Schilling, a consultant cardiologist also tweeted with the caption : "@NightingaleLDN is now open to help London. Here is the first team coming on duty."
Last week, the Prince of Wales officially declared the Nightingale open via video link from his Scottish home, saying it "offers us an intensely practical message of hope for those who will need it most at this time of national suffering".
More than 16,000 members of staff will be needed to run the facility when it reaches full capacity and members of the army worked 15-hour days so it is finished as soon as possible.
The Nightingale will become one of the biggest hospitals in the world, according to its chief operating officer Natalie Forrest.
