It may only be a flying visit, but President Trump is packing a lot in when he jets into Stansted airport this afternoon. Here's what his trip has in store.
Dinner at Blenheim Thursday Afternoon
He and the first lady, Melania, will have a meet and greet at the new US embassy in London – a project that the president previously criticised as being too expensive and in a "lousy" and "off" location.
They will also attend a black-tie dinner at Blenheim Palace in Oxfordshire, hosted by the prime minister.
The stately home is the birthplace of Winston Churchill and a UNESCO heritage site.
Mr Trump will be treated to a military ceremony in the Great Court, with a performance of the Liberty Fanfare, Amazing Grace, and the US national anthem by the bands of the Scots, Irish and Welsh Guards.
Leaders from a broad range of business sectors will be there in an event to celebrate UK-US business ties.
Stay at the ambassador's residence Thursday night
After a lavish dinner, the president will head to central London to spend the night at Winfield House – the US ambassador's residence in Regent's Park.
Heavy security has been set up around the residence, which has the second-biggest private garden in the country.
Meeting with Theresa May Friday morning
Mr Trumpwill again meet the prime minister – at the Royal Military Academy in Sandhurst.
The leaders will watch a demonstration of the UK's military capabilities and integrated UK-US military training.
They will then head to Mrs May's country retreat of Chequers for what Downing Street has described as "substantive bilateral talks on a range of foreign policy issues".
It could be an awkward working lunch considering Mr Trump's tariff hikes on UK and European products – something Mrs May has called "unjustified".
The president also raised eyebrows a few days ago by saying the UK was "in turmoil" in reference to the Brexit-related resignations.
Women's protest march begins Friday 11:00
Meanwhile, in London, two large demonstrations against the president will start to wind their way through the capital – and a "blimp" of Mr Trump as a snarling baby will fly near parliament in the morning.
Organisers say hundreds of thousands could take part.
Meeting the Queen Friday afternoon
After his appointment with the PM, Mr Trump and Melania will head to Windsor Castle to meet the Queen.
Ahead of the visit, ambassador Woody Johnson told Sky News meeting the monarch was "job one" for the president and "very symbolic".
A guard of honour will give a royal salute to the president and the US national anthem will be played, before Mr Trump and the Queen have tea inside the castle.
In the evening, Mr Trump and the first lady will leave for Scotland where they will be welcomed by David Mundell, the Secretary of State for Scotland.
A spot of golf? Saturday
It is likely Mr Trump will fit in a round or two of golf as he owns two golf courses in Scotland, including the Trump International Golf Links in Aberdeen.
According to the Trump Golf Count, he has visited clubs 113 times since taking office, and there's evidence he played golf 56 times.
The president is due to leave the UK on Sunday, with a summit with President Putin next on the cards.