Julie, visiting Washington DC with her husband, Robert, to celebrate their recent marriage, was unconvinced. “The irony,” she said. “It’s neither safe, nor beautiful.”

A chain-link fence surrounded the square, closing the site off from the public as it underwent refurbishment on the orders of Donald Trump.

It is one of many locations across the city currently under renovation, or construction, as Trump tries to put his stamp on the capital in time for the US’s forthcoming 250th anniversary celebrations.

Local preservationists say Julie’s withering verdict is widely shared.

“It is a different city right now,” said Rebecca Miller, executive director of the DC Preservation League, a city heritage group. “There are visitors from out of town who are disappointed that they’re only here for a few days, and there’s so much construction going on at the moment.

“This is a once-in-a-lifetime trip for some people, and to have it marred down with not being able to access certain sites can be really disappointing.”

Among a flurry of expensive projects, the US president has ordered the East Wing of the White House demolished to make way for a massive ballroom. Recently disclosed figures reveal the work is projected to cost $600m, with half the bill footed by taxpayers, contradicting Trump’s claim that the price tag would be $400m and met by private donors.

The National Park Service has been restoring fountains across the city, too, making them flow once again in time for the country’s birthday.

The administration also commissioned a restoration of the reflecting pool on the National Mall, which links the Lincoln Memorial with the George Washington monument, to repair the effects of discoloring algae. And plans have been unveiled for a 250ft triumphal arch south of the Potomac River, near Arlington national cemetery, which critics say would transform Washington’s low-rise skyline for the worse.

A simple recitation of the projects does not convey the temporary air that this frenzy of renovations has bestowed upon a historic area that has long drawn tourists from across the world.

Until its recent completion, the reflecting pool was for weeks a site of frenetic activity from workers repainting and re-coating its surface. The view for visitors was obscured by a fence covered by black tarpaulin. (Upon completion of a project Trump said would turn the pool “American-flag blue”, algae turned the water green.)

The transitory aura is compounded by renovations on the neighboring Arlington Memorial Bridge, a neoclassical structure built in 1932 whose columns and gold statues are also covered by tarpaulin.

Nearby, two projects unconnected to the administration – a memorial to veterans of the 1990-1991 Gulf war, and the Potomac River tunnel project, an infrastructure scheme aimed at reducing sewage overflows – add to the building site atmosphere.

It is more intense still near the White House, which is overshadowed by a large crane.

In recent weeks, the area has resembled an exclusion zone, with extended areas previously open to the public – from the Ellipse south of the White House to Lafayette Square at the north and encompassing parts of Pennsylvania Avenue – sealed off.

Lafayette Square, a 7-acre site featuring fountains and statues of the heroes of the American revolution, forming part of the larger President’s Park, is subject to renovations carried out under a $17m contract awarded on a no-bids basis to Clark Construction, the same company undertaking the White House ballroom project.

Scenes of visitors – like Robert and Julie – squinting for a better view have become commonplace.

“Everything that I’ve seen is to honor Donald Trump, not America’s 250th anniversary,” said Robert, a retired US history professor at a private college in Brooklyn, who like Julie declined to provide a second name.

Trump’s claims of grandeur outstripped those of King George III, the British monarch at the time of the Declaration of Independence, Robert suggested. “We have the irony of a man who has the instincts of an absolute monarch presiding over the celebration of our separation from a constitutional monarch,” he said. “It’s quite something.”

A block away, on 17th Street, Norma Roth, a 62-year-old children’s book author from Tampa, gaped at scores of temporary toilets – known colloquially as “Porta Potties” – which were installed on the Ellipse for the Ultimate Fighting Championship (UFC) on the White House’s South Lawn, which took place on 14 June, on Trump’s birthday.

“It’s so symbolic of what he’s doing to the country. It’s like he’s shitting all over our nation’s capital,” she said.

Wearing an “Elections Matter” T-shirt from a recent Bruce Springsteen concert, Roth called the exclusion area around the White House a denial of the free-speech values she taught her three children.

“They didn’t like George W Bush, but my husband and I explained to them what was meant by freedom: that you are allowed to protest and speak your mind,” she said. “So they stood in front of the White House and gave the thumbs down. You can’t do that now. It’s like we are under occupation.”

About a mile away, Mark, 68, a retired lawyer visiting Washington from his current home in Paris, took selfies at the reflecting pool, where he recalled being forced to stand during the 1976 bicentennial celebrations because of the vast crowds.

He voiced disappointment at the results of the recent work, costing $13.1m and leaving the surface water looking black under a slightly overcast light rather than the “American-flag blue” trumpeted by the president. “I don’t know if it’s a success or failure, but it doesn’t look as blue as I imagined,” he said.

Visitors were much rarer across the Potomac near the site of the proposed arch, which critics have dubbed the “Arc de Trump”, in mocking reference to Paris’s Arc de Triomphe.

Costing an estimated $100m, the arch would be built on a large roundabout that is now a busy traffic intersection. The few who passed expressed surprise and bemusement at the idea of the imposing structure.

Gabe Adame and his wife, Beth, both 43, from Corpus Christi in Texas and visiting the capital for the first time, reacted positively. “The whole area feels like a blank canvas and unfinished. It would be a good addition,” said Gabe, an instrumentation manager for an oil and natural gas company, who said he was a Trump supporter.

But Oliver, a 42-year-old worker for a nongovernment organization, said placing a towering structure at the gateway to the city could obscure more famous long-established landmarks. “I think it could be an obstruction to the main body of Washington, which is the George Washington monument,” he said. “The Lincoln Memorial has been with us for 150 years.”

That argument has been central to the objections of local heritage campaigners, who had until 15 June to make comment on the proposal under the planning schedule. “What is currently proposed does fundamentally cut off the sight line, unless you’re walking down the absolute center of Memorial Bridge,” said Miller, of the DC Preservation League.

About 600 letters of objection have been sent to the US Commission of Fine Arts, while congressional Democrats have introduced legislation to defund the project on the ground that it does not seek approval of Congress.

The White House argues that such approval is already granted under a 1925 report allowing for two 166-columns connected to the Arlington Memorial Bridge.

Miller dismissed that contention. “What they’re proposing is not the columns that were authorized for that design,” she said. “The columns [that were authorized] were on either side of the bridge, not on the traffic circle. It was designed in a very different way. That is not congressional authorization for them to build the arch.”

With large areas of the National Mall still cordoned off for the Great American State Fair, a 16-day exposition due to start on 25 June, Angie Clark, a molecular biologist from Salt Lake City visiting Washington for a scientific conference, complained of a “forbidding” atmosphere.

“I’ve been here many times before, and I have never imagined that I would be so completely locked out of everything,” she said. “It feels exclusive, and not in a good way. Maybe once the party starts up, it will be better.”