carving territory out of the East Riding of Yorkshire and of northern Lindsey respectively. Avon lumped Bristol, formerly a county borough within Gloucestershire, together with Bath, a former county borough in Somerset. Both these creations were to disappear in further local government reforms in the 1990s. Amendment and adaptation The system established by the Act was not to last. In England a series of incremental measures amended it. First, the county councils of the metropolitan counties, as well as the Greater London Council, were abolished in 1986 by Margaret Thatcher's government with the Local Government Act 1985, effectively re-establishing county borough status for the metropolitan boroughs. Second, a review of local government outside the metropolitan counties was announced in 1989. The local government reform in the 1990s led to the creation of many new unitary authorities, and the complete abolition of Avon, Cleveland, Hereford and Worcester and Humberside. Names such as Herefordshire and the East Riding of Yorkshire reappeared as local government entities, although often with new boundaries. Several former county boroughs such as Derby, Leicester and Stoke-on-Trent regained unitary status. Additionally, another wave of unitary authorities was formed in 2009. In Wales there was a more radical change in policy with the two-tier system entirely abolished in 1996, and replaced with the current principal areas of Wales. The 1974 counties in Wales have been retained as preserved counties for various purposes, notably as ceremonial counties, albeit with substantive border revisions. See also Local Government Boundary Commission for England (1972) Local Government Act (Northern Ireland) 1972 References External links Text of the Act United Kingdom Acts of Parliament 1972 Local government legislation in England and Wales Acts of the Parliament of the United Kingdom concerning England and Wales 1972 in England 1972 in Wales October 1972 events in the United Kingdom