The Tumulus is a raised part of Hampstead Heath that was once thought to have been the burial mound of Boudicca. More recently, there was a theory that it might have been an 18th-century rubbish heap. Now, we north Londoners are reluctantly coming round to the idea that it could just be a hill.

Either way, I stood on top of it in the middle of last week, and looked around the heath in all directions; there was not a single

person in sight. I thought of the previous evening, and how I had

walked through Highgate in the lonely, wistful mood I associate with British Sunday evenings of the 1970s. The roads had looked clean and wide because of the lack of traffic. For the past two days, my phone had not rung, and "No new messages" had obstinately flashed up every time I had checked my e-mails. (I'd like to customise that, incidentally, to say something a little more emollient, such as "No new messages but it's early days"). On each of those two afternoons, I'd reached such a point of inertia by 2.30pm that I had simply crawled under the duvet in my clothes and gone to sleep . . . And by now I'm sure that the middle-class parents among New Statesman readers will have diagnosed the cause of this torpor. Yes, it was half-term.

I walked on from the Tumulus towards Hampstead. On Downshire Hill, my usual approach to NW3, I saw one man. He was removing wellington boots from the back of his estate car, which carried a sticker showing a panda, and the words "I'm working for a living planet". He was an alternative type, I realised. He probably didn't even know it was half-term and that he shouldn't have been where he was.

Climbing Rosslyn Hill, I reflected that in most parts of Britain, you would, if anything, notice more people about during the half-term holidays. There'd be schoolchildren destroying things on street corners and shouting abusive remarks at passers-by who, a second earlier, had been thinking: "Perhaps I underestimated those kids: they didn't say anything offensive to me this time." But is that worse than being left behind in middle-class north London when everyone else has gone skiing or to their second homes in the country? I'm not sure.

I've often heard adults who live around here saying that the first half-term of the year is the holiday they feel most in need of. It is, after all, a full five weeks since the end of their extended Christmas break, and that's a long time to be continuously making extremely large sums of money.

In the centre of Hampstead, I noticed that a couple of my favourite shops were closed for lunch. They don't usually do that. I walked into the local Cafe Rouge. In the front part of the premises there were 20 tables, four of them occupied. I sat down, and listened to the man next to me, who was chatting up a young woman.

He did not look as though he was from Hampstead, and my suspicion was confirmed when he asked the waiter for "a white wine spritzer made with very sweet white wine" - one of the most unimpressive drinks orders I have ever overheard. It was in any case self-evident that he wasn't from Hampstead; he wouldn't have been around if he was. At another of the tables sat two women. After they'd finished eating, they ordered another bottle of wine. No two Hampstead women would have done that, or if they had done, it would have signified a major crisis in their lives - they would have been the Thelma and Louise of NW3. But these two women were clearly foreign, and they didn't know about half-term. Or perhaps they were here because it was half-term where they lived.

After my lunch, I returned to the quiet streets of Highgate with a strange thought: I was actually looking forward to the return of the 4x4s.