President Donald and first lady Melania Trump landed at Stansted Airport near London Monday morning.
The first lady sported an eye-catching Burberry blouse for her British arrival.
After landing, the Trumps traveled on the Marine One helicopter to Buckingham Palace to start the festivities.
Charles, Prince of Wales and Camilla, Duchess of Cornwall, were there to greet them. Melania had changed outfits into a bespoke Dolce and Gabbana dress and matching Hervé Pierre hat.
next slide will load in 15 secondsSkip AdSkip AdThe president accompanied Prince Charles on inspecting the Guard of Honor formed by Grenadier Guards in their traditional bearskin hats.
The first couple then joined Queen Elizabeth II outside the palace.
Members of the King's Troop Royal Horse Artillery performed a gun salute to kick off Trump's visit and the 66th anniversary of Queen Elizabeth's coronation.
The five leaders appeared side-by-side in front of the guard before entering the palace.
Trump's eldest daughter and adviser Ivanka was also spotted in tow with her husband and senior White House adviser Jared Kushner, upstairs the palace looking out the window.
next slide will load in 15 secondsSkip AdSkip AdThe first couple headed inside the palace with the queen to view historical artifacts and artwork in the Royal Collection.
Prince Harry also joined the Trumps to view items from the palace's Royal Collection.
The president and first lady then moved on to visit Westminster Abbey, the first of several stops at major London landmarks they're slated to make.
The official state visit comes nearly two years after the president was initially invited. Protesters are expected to welcome the president with much controversy and ceremony, including displaying a 20-foot inflatable blimp of Trump looking like a baby.
Trump met the queen last year, but it was a more informal visit at Windsor Castle, as opposed to a formal state visit.
next slide will load in 15 secondsSkip AdSkip AdInternational media tuned into Trump's trip, as he's expected to raise issues including trade policy and Brexit over the next few days.