Civil parishes do not cover the whole of England. There are none in Greater London and very few in the other conurbations. Civil parishes vary greatly in size: many cover tiny hamlets with populations of less than 100, whereas some large parishes cover towns with populations of tens of thousands. Weston-super-Mare, with a population of 71,758, is the most populous civil parish. In many cases, several small villages are in a single parish. Large urban areas are mostly unparished, as the government at the time of the Local Government Act 1972 discouraged their creation for large towns or their suburbs, but there is generally nothing to stop their establishment. For example, Birmingham has a parish, New Frankley, whilst Oxford has four, and Northampton has seven. Parishes could not however be established in London until the changing of the law in 2007 and as yet none have been established there.