List of smallest cities in the United Kingdom in the context of "Districts of England"

The City of London (often known as the City or the Square Mile) is a city, ceremonial county and local government district in England. Established by the Romans around 47 AD as Londinium, it forms the historic centre of the wider London metropolis. Surrounded by the modern ceremonial county of Greater London, from which it remains separate, the City is a unique local authority area governed by the City of London Corporation, which is led by the Lord Mayor of London; although it forms part of the region governed by the Greater London Authority.

Nicknamed the Square Mile, the City of London has an area of 1.12 sq mi (716.80 acres; 2.90 km), making it the smallest city in the United Kingdom. It had a population of 8,583 at the 2021 census, however over 500,000 people were employed in the area as of 2019.

St Davids or St David's (Welsh: Tyddewi, [tiː ˈðɛwi], lit. "David's house”) is a cathedral city in Pembrokeshire, Wales. It lies on the River Alun and is part of the community of St Davids and the Cathedral Close. It is the resting place of Saint David, Wales's patron saint, and named after him.

St Davids is the United Kingdom's smallest city by population (number of residents within the wider community was 1,751 in 2021) and urban area, but it is not the smallest city by local authority boundary area (which is the City of London). St Davids was given city status in the 12th century. This does not derive automatically, but in England and Wales was traditionally given to cathedral towns under practices laid down in the early 1540s, when Henry VIII founded dioceses. City status was lost in 1886, but restored in 1994 at the request of Queen Elizabeth II.

This is a list of the most populous civil parishes in England. It includes all civil parishes with populations over 30,000, representing less than 1% of all civil parishes but almost 3% of the population.

Lichfield, Hereford and Salisbury are in addition to being some of the most populous civil parishes in England, among the smallest cities.

Wells (/wɛlz/) is a cathedral city and civil parish in Somerset, located on the southern edge of the Mendip Hills, 21 miles (34 km) south-east of Weston-super-Mare, 22 mi (35 km) south-west of Bath and 23 mi (37 km) south of Bristol. Although the population recorded in the 2021 census was only 11,145, and with a built-up area of just 3.244 km (1.253 sq mi), Wells has had city status since medieval times, because of the presence of Wells Cathedral. Often described as England's smallest city, it is actually the second smallest to the City of London in area and population, but unlike London it is not part of a larger urban agglomeration.

Wells takes its name from three holy wells dedicated to Saint Andrew that lie within the grounds of the Bishop's Palace and cathedral and supply water to the marketplace. A small Roman settlement surrounded them, which grew in importance and size under the Anglo-Saxons when King Ine of Wessex founded a minster church there in 704. The community became a trading centre based on cloth making and Wells is notable for its 17th-century involvement in both the English Civil War and the Monmouth Rebellion. In the 19th century, transport infrastructure improved with stations on three different railway lines. However, following the Beeching axe in 1964 the city has been without a railway link.

Wales has seven cities as of September 2022. Bangor is Wales' oldest cathedral city, whereas St Davids is the smallest city in the United Kingdom. Cardiff is the capital city of Wales and its most-populous, followed by Swansea the second most-populous. Since 2000, Welsh towns have submitted bids to be awarded city status as part of jubilees of the reigning British monarch or for other events, such as the millennium celebrations, with Newport, St Asaph and Wrexham awarded city status through these contests. Wrexham is the newest to hold the status, being awarded it in September 2022 as part of the Platinum Jubilee Civic Honours of Queen Elizabeth II.