The ornate cast iron gates and railings across the Whitehall and St James’s Park entrances to Downing Street were installed in 1989, at a time when the threat of terrorist attack was high, particularly by the Provisional Irish Republican Army (or IRA).
The British Prime Minister’s official London residence at 10 Downing Street, with its iconic black door, is arguably one of the most recognisable political buildings in the world. While vehicular access to Downing Street was restricted by barriers in 1973, until the early 1980s, the public could walk freely down the street and pose for photographs in front of Number 10.
This changed in 1982, when moveable barriers were erected due to a perceived increase in the threat of terrorism, and public access to Downing Street was restricted, permanently so with the gates installed in 1989. Technically a public right of way remains, but authorities can use common law breach-of-the-peace powers and anti-terrorism legislation to limit access to pass holders, scheduled visitors and members of the accredited media.