Donald Trump is playing a final round of golf at his Turnberry golf course after spending a second night in Scotland.
The US president will leave the UK later ahead of a summit with Russian President Vladimir Putin in Helsinki.
There is tight security at the Ayrshire resort but on Friday evening a protester managed to paraglide over it.
Police Scotland said a 55-year-old man has been arrested in connection with the incident.
Mr Trump has been staying at his Turnberry hotel on the Ayrshire coast during the private leg of his UK visit.
He was heckled by protesters as he played golf on Saturday afternoon after they gathered around the perimeter of the resort.
He waved as they heckled him from a hill overlooking the Ailsa championship course.
In Edinburgh thousands of people marched through the city in a demonstration against the president’s controversial visit to the UK.
They waved placards as they gathered in the capital’s Meadows, where two giant nappy-clad baby Trump balloons were inflated.
In a tweet on Saturday, Mr Trump said he was at Turnberry “for two days of meetings, calls and hopefully some golf”.
“The weather is beautiful and this place is incredible,” he added. “Tomorrow I go to Helsinki for a Monday meeting with Vladimir Putin.”
There have been calls for Monday’s meeting between the US and Russian presidents to be cancelled, after the US charged 12 Russian intelligence officers with election interference.
But White House spokeswoman Sarah Sanders has said the meeting will go ahead as planned in Helsinki.
And Mr Trump used Twitter to criticise the administration of his predecessor Barack Obama over alleged Russian hacking to help him win the 2016 presidential election.
“Why didn’t they do something about it?” he tweeted, adding that Mr Obama had been told about it before the vote.
Police estimated that about 9,000 people took part in the march through Edinburgh, which they said “passed without incident”.
They gathered at the Scottish Parliament, before walking to the city’s meadows area for a “carnival of resistance”.
At Turnberry, protesters climbed a hill near the golf course to ensure the president could see their placards and banners.
As he took to the golf course with his son, Eric, they branded him a “racist”, shouting: “No Trump, no KKK, no racist USA.”
The president and his wife Melania arrived in Scotland on board Air Force One on Friday evening, before travelling by motorcade to the Trump Turnberry resort – one of two Scottish golf courses he owns.
There is a massive security operation in place at the complex on the Ayrshire coast but shortly after he arrived a paraglider flew over the area with a sign claiming Mr Trump was “well below par”.
It comes after the president spent Friday meeting both Theresa May and the Queen on what is Mr Trump’s first visit to the UK as president.
Supporters of Mr Trump gathered in London on Saturday, the day after an estimated 100,000-plus rallied through London in opposition to the US president.