Real life on hold as streets empty on a surreal Saturday afternoon

It was supposed to be Open House in London yesterday. Closed House was more like it.

Open House is when 500 buildings not normally accessible to the public throw open their doors to reveal architectural glories within. It has become one of the most popular events in the capital's calendar, drawing the curious by the thousand.

But there was disappointment for those who had hoped it would give them something to think about other than imminent war. With the police putting the capital on full terrorist alert, government, military and media buildings that had been part of the scheme were forced to pull out. These included the Foreign Office and Treasury buildings in Whitehall, the scene of a CND anti-war vigil numbering about 2,000 black-clad protesters.

They broke their silence to cheer and applaud when a delegation entered Downing Street led by two veteran peace campaigners – Bruce Kent and the recently retired MP Tony Benn. "We have to learn from the past,'' Mr Benn said. "It's talking that solves these things not war.''

A taxi driver confirmed that there was more to the quiet in the centre of the city than the observance of Car-Free Day. "Been like it all week,'' he said as he sped off across Trafalgar Square. There were moments when nearby St Martin's Lane, usually jammed with traffic, was devoid of moving vehicles. A long-lost vision of the capital was reappearing before one's eyes, and in the soft light of a beautiful September day reality seemed to have been suspended.

The notion of a "national mood" can often seem misplaced. Not everyone was caught up in Diana fever after her death four years ago. But nobody is wondering now what all the fuss is about, even as people attempt to carry on as normal.

Jean Horsfall and Mike Brunt were down from Whaley Bridge, near Manchester. They are planning a trip to Australia next year and wanted to visit Australia House in the Strand, one of the London Open House sites. But it too turned out to be closed for security reasons. "So that didn't really take our minds off things,'' Ms Horsfall said. Now she is wondering if they will be making the trip at all. "Still, we have only put down a £10 deposit.''