In central London, on land the size of seven football fields, stands a mansion called Winfield House, the official residence of the US ambassador to the United Kingdom.

It is a majestic house and over the years it has been known. for hosting extraordinary parties, especially on July 4th, Independence Day.

Fashion elite, sports stars, and political leaders have all been hosted here. Even in 1825, when it was built, the mansion's primary use was entertaining.

President Donald Trump spent the first night of his state visit in the 35-room mansion. The Trumps also stayed there in 2019, as did the Bidens and Obamas before them.

"It's not just the ambassador's residence, but also a center for diplomatic hospitality," says Stephen Crisp, the estate's former head gardener, who worked there for 37 years until his retirement last year.

But Winfield is not a tourist attraction. The Friends of Regent's Park organization has previously organized guided tours of the mansion's gardens, but this year the ambassador refused permission.

From the street, the house is invisible. It's surrounded by woodland and enjoys a great deal of privacy despite its central London location.

"It's very, very difficult to get into. I consider myself proud to have managed to do so," says Viv Ward, events organizer for Friends of Regent's Park. She describes the house as "magnificent" and expresses her admiration for the location.

Tours to Winfield only allow you to see the ground floor, which is primarily a "very elegant" reception area, and the gardens. The first floor houses the ambassador's personal apartments.

As the ambassador's residence and the venue for most American receptions, schedules are tight.

The property boasts the second-largest private garden in central London, Crisp says. It has lawns, paved walkways, sculptures, and even space for helicopters to land.

Owned by a Billionaire

American socialite Barbara Hutton sold Winfield to the US government for just one dollar in 1946, in an offer then-President Harry S. Truman described as “most generous and patriotic.”

Hutton had purchased the house ten years earlier after it was partially destroyed in a fire.

The Crown Property Commission authorized her to tear it down and rebuild in the iconic red brick Georgian style that remains to this day.

She named it after her grandfather, Frank Winfield Woolworth, founder of the Woolworth's chain of stores.

With World War II looming and her second marriage failing, Hutton returned to the United States with her son in 1939.

It was later revealed that this was when she met her next husband, the actor Cary Grant, who he reportedly stayed at the mansion with her.

During the war, Winfield was requisitioned by the Royal Air Force's protective balloon unit, and officers are said to have played football in the gardens.

Hutton returned to London to see what remained of the site at the end of the war following German bombing. She called her solicitor and requested that the mansion be handed over to the American government for repairs, and it has been used as an official ambassadorial residence ever since.

History is in the walls of Winfield. The original building was called St Dunstan's and, according to Friends of Regent's Park, it was used for blind veterans of the First World War. A charity of that name still exists.

Referring to American presidents, Crisp says: “At some point, everyone comes, at least once.”

He explains that he met Trump and his wife Melania during their previous state visit in 2019, which was “a bit surreal.” They dined at the estate with Queen Camilla and King Charles III before he ascended the throne.

An iconic image of Mikhail Gorbachev, the last Soviet leader, and US President George HW Bush might be one of the house's most famous documents. The two held a joint press conference there during the G7 summit in 1991.

Politicians have long used it for key moments, such as international summits, large state dinners and meetings of wartime leaders.

Extreme Security

Information about security for presidential visits is confidential and often never disclosed. But Ward shared details of the daily routine at the house.

“Security is incredible—for example, I had to send the embassy a list of attendees,” he says, explaining that armed guards at Winfield's gates had to be shown photo ID.

And if you wanted to leave early, an armed officer had to escort you off the premises.

Winfield House has hosted a wide range of events, Crisp says.

Take That, Duran Duran, the Foo Fighters, Ed Sheeran, and Bastille have all performed there, sometimes in the garden and sometimes in the house, he notes.

It has also hosted sporting events, including the Duke of Sussex's Invictus Games reception.

Michelle Obama took an active part in one sporting event, even playing tug-of-war alongside some celebrity guests.

Fashion royalty has also invaded the halls of Winfield. Former Vogue editor Alexandra Shulman co-hosted a London Fashion Week kick-off party with the then-ambassador. A Spice Girl was also spotted.

Some events have had thousands of guests, says Crisp, and Fourth of July parties often drew 3,000 to 4,000 people.

The place is something of an escape. “You'd never guess you were in central London,” says Ward.

But is there anything disappointing about the house? According to Ward, its entrance is “quite modest” compared to the rest of Winfield.

“It's a suitable size for large limousines, but a brigade of guards wouldn't be able to walk in.”

Additional reporting: Grace Dean

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