Central London and its surrounding districts are divided into 32 boroughs (33, counting The City of London). More useful for navigating, however, are the subdivisions of London into postal districts. Throughout the guide we've given the abbreviated postal code for most listings. The first one or two letters give the location: N means north, NW means northwest, and so on. Don't expect the numbering to be logical, however. (You won't, for example, find W2 next to W3.) The general rule is that the lower numbers, such as W1 or SW1, are closest to the city center.