PinnedUpdated Sept. 17, 2025, 5:47 a.m. ETPresident Trump and the first lady, Melania Trump, are set to spend the day with the British royal family on Wednesday at Windsor Castle outside of London, beginning a two-day state visit swaddled in the kind of pomp and grandeur that so thrills this president.There will be a carriage ride through the Windsor estate and a state dinner at the 900-year-old castle hosted by King Charles III. In between, Mr. and Mrs. Trump are expected to visit St. George’s Chapel to lay a wreath at the tomb of Queen Elizabeth II. The Trumps plan to spend the night at Windsor Castle before the president meets with Prime Minister Keir Starmer on Thursday.The state visit is part of an effort by the British government to engage with a president who has returned to office less interested than ever in maintaining the post-World War II order. The fact that Mr. Trump has been invited to Britain for a second state visit — after his first in 2019 — is itself a rare diplomatic gesture that no other American president has enjoyed.“My relationship is very good with the U.K., and Charles, as you know, who’s now king, is my friend,” Mr. Trump said from the south lawn of the White House on Tuesday morning before departing for Britain. “And it’s the first time this has ever happened where somebody was honored twice, so it’s a great honor.”Evidently he was charmed by the choice of venue. “They say Windsor Castle is the ultimate, right?” he asked. (Buckingham Palace, where his first state visit took place, is undergoing renovations.)Here’s what else to know:Two-day visit: After the royal extravaganza on Wednesday, the president is scheduled to travel to Chequers, the prime minister’s country estate, on Thursday to meet with Prime Minister Keir Starmer. The two leaders are expected to sign a handful of deals, and to hold a joint news conference.U.K. upheaval: Over the weekend, the anti-immigrant agitator Tommy Robinson led a protest of more than 100,000 people through London — one of the largest far-right demonstrations in Britain’s history. Mr. Trump’s former adviser, Elon Musk, who has repeatedly amplified Mr. Robinson on social media, delivered a virtual address to the demonstrators in which he called for a change in government and used alarmist rhetoric about immigration, telling Britons: “Whether you choose violence or not, violence is coming to you.” Mr. Starmer condemned the remarks.Epstein ties: Though Mr. Trump might have hoped to leave behind the political tensions at home, the drama over the deceased sex offender Jeffrey Epstein will simmer in the background on his trip. British activists protested Mr. Trump’s arrival on Tuesday by projecting a picture of the president with Mr. Epstein onto the walls of Windsor Castle and unrolling a massive banner of the picture on the castle’s lawn. Last week, Mr. Starmer fired his ambassador to Washington, Peter Mandelson, over his ties to Mr. Epstein. Both Mr. Trump and Mr. Starmer were expected to face questions about the ongoing Epstein saga.Sept. 17, 2025, 5:57 a.m. ETLondon is home to Google’s A.I. research lab DeepMind. Credit...Benjamin Quinton for The New York TimesPresident Trump’s visit to Britain this week is being used by some of America’s biggest tech companies to announce more than $40 billion in investments for artificial intelligence, data centers and other new technologies.Microsoft said it would invest about $30 billion in Britain over four years, including developing a new supercomputer with the British company Nscale. Google said it was opening a new data center as part of a two-year investment worth about $6.8 billion. OpenAI and the semiconductor company Nvidia are developing a new A.I. data center called Stargate UK with Nscale.Mr. Trump’s two-day state visit, hosted by King Charles III, is following a similar script as his May trip to the Persian Gulf. In the United Arab Emirates and Saudi Arabia, Mr. Trump met with government officials and members of their royal families while helping forge business deals involving American tech companies.Mr. Trump is expected to be joined in Britain by tech executives, including Satya Nadella of Microsoft and Sam Altman of OpenAI.This week’s deals strengthen the economic and technological ties between the United States and Britain three months after the countries reached a trade deal. The agreement “marks a generational step change in our relationship with the U.S.,” Prime Minister Keir Starmer of Britain said in a statement.Microsoft, Google and others have been expanding in Europe even as countries in the region become more concerned about dependence on American tech companies for key services. European officials have sought assurances from American firms about the protection of data and the storage of information in data centers in Europe.British officials said the announcements this week will help create 5,000 jobs and expand research in areas like A.I., quantum computing, drug discovery and nuclear energy. The deals will bring Britain about 120,000 of Nvidia’s advanced semiconductors that are needed for A.I. development, which the government said will be the biggest supply in Europe to date.Sept. 17, 2025, 4:26 a.m. ETVideoBritish protesters projected images of President Trump and Jeffrey Epstein onto Windsor Castle on Tuesday night before the president arrived for a state visit. More protests are planned for Wednesday.CreditCredit...Phil Noble/ReutersBritish activists upset about President Trump’s state visit this week protested his arrival by projecting a picture of Mr. Trump with Jeffrey Epstein on the walls of Windsor Castle and unrolling a massive banner of the picture on the castle’s grassy lawn.The president and Melania Trump, the first lady, arrived in London on Tuesday night. They are scheduled to spend Wednesday at Windsor Castle, hosted by King Charles III and Queen Camilla. Mr. Trump will also meet Prime Minister Keir Starmer at his country residence, Chequers, on Thursday.Police intervened to stop both political stunts quickly and made arrests over the projection. Representatives of the group behind the banner said they had achieved their goal of seeking to embarrass the president by noting his one-time friendship with the convicted sex trafficker.The banner was created by the group Everyone Hates Elon, which was behind similar protests in Britain against Elon Musk, the billionaire tech mogul.Mr. Trump’s trip this week to Britain, where he is broadly unpopular, has also spurred a television special by Channel 4, a public broadcaster, aimed at fact-checking questionable claims that he made as president, as well as a planned demonstration in the streets of London on Wednesday.His first state visit in 2019 drew large crowds of protesters offering a similar sentiment: He is unwelcome in Britain.Mr. Trump has in recent months struggled to evade the public’s scrutiny over his ties to Mr. Epstein, who was arrested on charges of sex trafficking in 2019 before dying in prison. Lawmakers recently released documents showing the financier’s association to Mr. Trump, who has repeatedly referred to the Epstein case as a “hoax.”The banner rolled out by Everyone Hates Elon was about 65 feet long and 65 feet wide. It was paid for by about 2,000 crowdsourced donors, the spokeswoman said.The images of Mr. Trump and Mr. Epstein were apparently projected onto the towers of Windsor Castle by a different group called Led By Donkeys, who have performed similar stunts in the past. The images were also posted to the group’s Instagram account.Felicity Parker, the chief superintendent of the Thames Valley Police, said in a statement that officers had “responded swiftly to stop the projection” and arrested four people on suspicion of malicious communications, a low-level offense.On the first day of Mr. Trump’s state visit on Wednesday, protesters were expected to gather in London and march to Parliament Square.On Wednesday night, Channel 4 was scheduled to air over several hours a reel of what it called the “untruths, falsehoods and distortions” that Mr. Trump has spoken since January, punctuated by fact checks.“We hope it will remind viewers how disorientating and dangerous the world becomes when the most powerful man on earth shows little regard for the truth,” Ian Katz, Channel 4’s chief content officer, said in a statement.Sept. 17, 2025, 3:58 a.m. ETPresident Donald Trump and first lady Melania Trump arriving at Stansted Airport, outside London, on Tuesday.Credit...Doug Mills/The New York TimesPresident Trump and his wife, Melania, arrived Tuesday night in Britain for a two-day state visit, hosted by King Charles and Queen Camilla. It is Mr. Trump’s second state visit, an unusual honor.When do the events begin?On Wednesday, a guard of honor will greet the Trumps as they arrive around midday at Windsor Castle, a royal home and fortress for more than 900 years. They will have lunch with the royal family, and Mr. Trump will watch a fly-past by the Red Arrows, the aerobatics display team of the Royal Air Force, and American F-35 military jets.There will also be a military event known as Beating Retreat, a colorful display of music and drill.On Wednesday evening, a traditional white-tie banquet will be held in Windsor Castle, where Mr. Trump and King Charles will give speeches.What happens Thursday?On Thursday, the president will travel to Chequers, the official country residence of Britain’s Prime Minister, Keir Starmer. They are expected to visit the Winston Churchill archives at Chequers and join a business reception.Mr. Trump and Mr. Starmer are also expected to hold a joint news conference on Thursday. The New York Times will livestream the news conference.Mrs. Trump will remain at Windsor, where she will see Queen Mary’s Dolls’ House with Queen Camilla, and later join Catherine, Princess of Wales, at Frogmore Gardens for an event with Britain’s Scouts Association.Are protests planned?Yes. On Wednesday, organizers have scheduled a demonstration in London culminating in a march to Parliament Square.But the state visit program has been designed to limit security risks, as well as minimize the opportunity for protesters to confront a president who is broadly unpopular with the British public. The carriage procession will take place inside the royal grounds at Windsor, and the formal agenda does not include events in central London.