As I walked towards the most famous front door in the world I wondered what I should do next.
I rather expected a bell which would ring out à la Big Ben – or at least a very sturdy knocker, possibly sculpted in the shape of Gladstone’s face.
But there was nothing obvious and the security guards who had X-rayed my possessions on entry to Downing Street hadn’t given me any clue.
So, let me tell you a secret – Number 10’s door opens automatically.
There is a very helpful chap on the other side, who asks visitors to deposit their mobile phones on arrival.
But he does not wear uniform akin to a Beefeater’s, which, bizarrely, is what I had expected.
A few years ago, I was invited by the Prime Minister’s team to join him (David Cameron) and six newspaper editors for a roundtable discussion. This was an important opportunity to discuss how the Leveson report would affect the regional press.
Thus, I was armed with questions which, I believed, were at the heart of future press freedom.
That seems all pompous and professional, doesn’t it?
In fact, I felt like the ultimate London tourist – the one with the backstage pass which money can’t buy.
I had arrived earlier than my fellow journalists, such was my excitement.
Thus, after arrival, I was directed to a small waiting room from where I could watch unsmiling people rush around with important-looking files under their arms.
Memories of Yes, Prime Minister came flooding back, except that the civil servants were very young compared to the days of Sir Humphrey.
Anyway, after being fetched from the waiting room I was delivered up the stairs where pictures of Prime Ministers past stared down. It would have been interesting to have been given a pub quiz sheet and seen how many I could have recognised.
In the 1970s, Harold Wilson sat down for beer and sandwiches with trade union leaders.
During my visit, there were prawn sandwiches, among others, and a variety of juices but no alcohol was offered.
Even if it had been, I would have declined, wishing to avoid garbling my words in front of the Prime Minister.
As we sated ourselves one could hear a crying baby in the background. I wondered whether it was Mr Cameron’s daughter, Florence, but she was two-and-a-half now, so I guess not.
And then, suddenly, the PM arrived and I was spouting on about Leveson.
At which point I had something akin to an out-of-body experience. There was I, the accidental tourist, son of a machine tool fitter, arguing about Government policy with the Prime Minister in Downing Street.
I may have been only 50 years old but in my head, I am still 18.
However, I am sure age and experience meant I wasn’t a nervous wreck while crossing swords with the PM. But they didn’t stop me being in awe of my surroundings.