Har Nof's main business quickly becomes clear as you walk along its streets: religion. The apartment blocks are interspersed with large buildings housing synagogues and yeshivas, and a further clue to Har Nof's make-up comes from the inscriptions outside many of them, proclaiming the origin of their funding: Antwerp, Paris, Mexico City, and many more far-flung places. Almost everybody in Har Nof is from somewhere else: the United States, Britain, France, South Africa, Australia, South America, and many of them are quite recent immigrants. Outside one rocky building site, a large notice announces a future development by the Jewish community of Venezuela, but I have seen no activity there in the five years we have been visiting Har Nof, probably because the Jews of Venezuela, who have undergone constant vilification at the hands of the governments of the late Hugo Chávez and his successor Nicolás Redondo, can't get their money out of their slowly disintegrating country.

During the day, the streets are quiet: everybody of all ages is studying. At lunchtime and in the late afternoon, they fill up, above all with children returning from school. The girls wear light-blue blouses with long sleeves and long dark-blue skirts, the boys dark-blue kippot (skullcaps). The men all wear the same sombre uniform: dark suits (though the jackets are usually discarded in hot weather), white shirts and wide black hats. They are not Hassids, with their long side curls and 18th-century Polish court dress to be found in many quarters of Jerusalem, notably Meah Shearim, close to the Old City, but like them they are all bearded and equally devoted to the study of Torah; they are generally described by outsiders as Haredi (literally, "one who trembles at the word of God"). The women dress modestly, with long dresses and headscarves or sheitels (wigs). All the young women are pushing buggies: Har Nof is packed with children. Families of ten are common. The large playground at the end of Daniel's street is packed with children, while the young women tend their babies and chat. American accents predominate: indeed, my two older grandchildren speak with a pronounced American twang, the dominant accent of their classmates. The apartment block stairwells echo with the distant sound of babies crying.

There is an air of reserve about Har Nof. People keep themselves to themselves, although occasionally a young American mother will exchange a few words as we push our kids on the swings. The place really comes alive on Shabbat. Traffic is forbidden (by municipal ordinance) and the streets throng with children playing, the older ones looking after their younger siblings. Occasionally a small boy will hurtle past on a makeshift trolley, without fear of crashing into a vehicle at the bottom of the hill, while the men walk to and from synagogue (Haredi women rarely attend). The one thing that irritates the tidy-minded outsider is the amount of litter in the streets, flowerbeds, everywhere: the Haredim seem to have no interest in the appearance of their public spaces, perhaps because they are so focused on spiritual matters (although the same can be said of most Israelis, religious or secular).

But if they don't care about appearances, they do care about each other. Whenever anyone is ill or in trouble, has suffered a bereavement or just given birth, the neighbours rally round, even when they barely know you. Each time my daughter-in-law Ruchy came home with a new baby, people would appear at the door with cooked meals for the freezer. She does the same for them once she's up and about again. When I last spoke to her, she was cooking for the family of one of the synagogue massacre victims, who had left ten children. A giant of a man, he was on an upper floor when the attackers burst in downstairs. Instead of saving himself, as he could easily have done, he raced downstairs to tackle them and was cut down.