ON FRIDAY AFTERNOON, 28 February 2003, after fifteen years of debate, planning, and construction, the north-west London eruv was declared to be ‘up’ and effective for the approaching sabbath, meaning that, by virtue of a conceptual halakhic device imposed on the urban structure, the fabric of the city could be regarded in Jewish law as a private domain (the technical term is reshut hayaḥid). This had tremendous consequences for sabbath-observant Orthodox Jews.

Structurally, the eruv (technically, eruvḥatserot, meaning ‘a mingling of courtyards’) is an urban space whose disparate areas are regarded halakhically as forming a single unit by virtue of the contiguity of its boundaries. An eruv can be built in a single street, uniting several dwellings on that street, or on a much larger scale, uniting many streets and households. Where the pre-existing urban features that can halakhically constitute boundaries (fencing, houses, hedges, railway lines, major roads, and bridges) are not fully contiguous, Jewish law can under certain circumstances allow for the boundary to be ‘completed’ by erecting poles linked with wire to close the gaps. It was the erection of some eighty poles in this way that permitted the creation of an eruv that encompasses an area of 6.5 square miles, including large parts of Hendon, Golders Green, Finchley, and Hampstead Garden Suburb, between them containing the majority of the Jewish population of north-west London.

To what end is this done? On the sabbath, all productive work is forbidden, but several other categories of activity are also suspended, including carrying objects from one domain to another. The prohibition on carrying applies not only to objects but also to people, and not only to carrying per se but also to pushing and throwing. Thus parents may not carry their infants or push them in a pram. The elderly may not walk with the assistance of canes, and wheelchair-bound people may not be pushed in their chairs or even propel them themselves. By creating a symbolic private domain, an eruv enables such acts to be undertaken on the sabbath within the parameters of Jewish law. This essay is about how the London eruv altered the experience of the sabbath for many local Jews by extending the concept of the Jewish home to the scale of the city. The effects of creating an