Urban District Councils could petition for a charter of incorporation, changing the status of the urban district to that of a Borough. The following districts became boroughs in this way: •
Bangor by letters patent dated 30 December 1927, taking effect on 23 January 1928; •
Coleraine by letters patent dated 29 December 1928, taking effect on 23 January 1929; •
Newtownards by letters patent dated 8 November 1937, taking effect on 23 May 1938; •
Ballymena by letters patent dated 21 December 1937, taking effect on 23 May 1939; •
Larne by letters patent dated 15 November 1938, taking effect on 23 May 1939; •
Portadown by letters patent dated 24 July 1947, taking effect on 2 October 1947; •
Enniskillen by letters patent dated 29 April 1949, taking effect on 30 May 1949; •
Carrickfergus by letters patent dated 27 May 1949, taking effect on 1 July 1949; •
Lurgan by letters patent dated 27 May 1949, taking effect on 7 July 1949; and •
Lisburn by letters patent dated 24 March 1964, taking effect on 2 June 1964. A small number of districts were abolished or created after 1921. The entire system of local government in Northern Ireland was overhauled by the
Local Government Act (Northern Ireland) 1972, which replaced the county boroughs, administrative counties, urban districts, and rural districts with 26 local government
districts. The new system came into effect on 1 October 1973. == County boroughs ==