Please answer the following question: Information: - The River Thames is a river that flows through southern England. At , it is the longest river entirely in England and the second longest in the United Kingdom, after the River Severn. It also flows through Oxford (where it is called Isis), Reading, Henley-on-Thames and Windsor. The lower reaches of the river are called the Tideway, derived from its long tidal reach up to Teddington Lock. It rises at Thames Head in Gloucestershire, and flows into the North Sea via the Thames Estuary. The Thames drains the whole of Greater London. - Yiewsley is a place in the London Borough of Hillingdon. Its name derives from the Anglo-Saxon "Wifeleslah": "Wifel's woodland clearing". Yiewsley was a chapelry in the ancient parish of Hillingdon, Middlesex. The population was recorded as 11,767 in 2008, by the Office for National Statistics. - Uxbridge is a town in west London, England, and the administrative headquarters of the London Borough of Hillingdon. Fifteen miles (24.1km) west-northwest of Charing Cross, it is one of the major metropolitan centres identified in the London Plan. Uxbridge historically formed part of the parish of Hillingdon in the county of Middlesex, and was a significant local commercial centre from an early time. As part of the suburban growth of London in the 20th century it expanded and increased in population, becoming a municipal borough in 1955, and has formed part of Greater London since 1965. It is a significant retail and commercial centre, and is the location of Brunel University and the Uxbridge campus of Buckinghamshire New University. The town is close to the boundary with Buckinghamshire, which is locally the River Colne. - London is the capital and most populous city of England and the United Kingdom, as well as the most populous city proper in the European Union. Standing on the River Thames in the south east of the island of Great Britain, London has been a major settlement for two millennia. It was founded by the Romans, who named it "Londinium". London's ancient core, the City of London, largely retains its medieval boundaries. Since at least the 19th century, "London" has also referred to the metropolis around this core, historically split between Middlesex, Essex, Surrey, Kent, and Hertfordshire, which today largely makes up Greater London, governed by the Mayor of London and the London Assembly. - Heathrow was a small hamlet in the ancient parish of Harmondsworth , Middlesex , England , on the outskirts of what is now Greater London . It was demolished in 1944 for the construction of London Heathrow Airport . The hamlet was a mile and a half east of Longford ; its site is now part of the London Borough of Hillingdon . - West Drayton is a suburban town in the London Borough of Hillingdon, England. Formerly part of the Yiewsley and West Drayton Urban District of Middlesex, the district became part of Greater London in 1965. - A borough is an administrative division in various English-speaking countries. In principle, the term "borough" designates a self-governing walled town, although in practice, official use of the term varies widely. - Ruislip is a town in West London, England, which is part of the London Borough of Hillingdon. - A barn is an agricultural building usually located on farms and used for various purposes. In the North American area, a barn refers to structures that house livestock, including cattle and horses, as well as equipment and fodder, and often grain. As a result, the term barn is often qualified e.g. tobacco barn, dairy barn, sheep barn, potato barn. In the British Isles, the term barn is restricted mainly to storage structures for unthreshed cereals and fodder, the terms byre or shippon being applied to cow shelters, whereas horses are kept in buildings known as stables. On the Continent, however, barns were often part of integrated structures known as byre-dwellings (or housebarns in US literature). In addition, barns may be used for equipment storage, as a covered workplace, and for activities such as threshing. - Harmondsworth is a village in the London Borough of Hillingdon with a short border to the south onto London Heathrow Airport. The village has no railway stations; however, it adjoins the M4 motorway and is bisected by its predecessor, the Bath Road. Harmondsworth is an ancient parish which once included the large hamlets of Heathrow, Longford and Sipson. Longford and Sipson have modern signposts and facilities as separate villages, remaining to a degree interdependent such as for schooling. Its great barn and its church are well-repaired medieval buildings in the village. The largest proportion of land in commercial use is related to air transport and hospitality. The village includes public parkland with footpaths and butts onto the River Colne and further land in its regional park to the west, within Colnbrook. - The City of London is a city and county within London. It constituted most of London from its settlement by the Romans in the 1st century AD to the Middle Ages, but the agglomeration has since grown far beyond the City's borders. The City is now only a tiny part of the metropolis of London, though it remains a notable part of central London. Administratively, it forms one of the 33 local authority districts of Greater London; however, the City of London is not a London borough, a status reserved for the other 32 districts (including London's only other city, the City of Westminster). - Middlesex (abbreviation: Middx) was a county in southeast England that is now mostly part of Greater London, with small sections in neighbouring counties. It was established in the Anglo-Saxon system from the territory of the Middle Saxons, and existed as an official unit until 1965. The historic county included land stretching north of the River Thames from east to west of the City of London with the rivers Colne and Lea and a ridge of hills as the other boundaries. The largely low-lying county, dominated by clay in its north and alluvium on gravel in its south, was the second smallest by area in 1831. - The M4 is a motorway which runs between London and South Wales in the United Kingdom. Major towns and cities along the route include Slough, Reading, Swindon, Bristol, Newport, Cardiff and Swansea. Originally referred to as the London-South Wales Motorway, the English section, including a suspension bridge over the River Severn, was constructed between 1965 and 1971; the Welsh element was completed in 1993. A new Severn bridge, known as the Second Severn Crossing, was opened in 1996 with the M4 rerouted to use it. - Sipson is a village in the historic county of Middlesex, England, but since 1965 has been administered as part of the London Borough of Hillingdon, the westernmost borough of Greater London. It is west of Charing Cross and near the north perimeter of London Heathrow Airport. - Heathrow Airport is a major international airport in London, England. Heathrow is the third busiest airport in the world by international passenger traffic (surpassed by Dubai International in 2014, and Hong Kong International in 2016), as well as the busiest airport in Europe by passenger traffic, and the sixth busiest airport in the world by total passenger traffic. In 2016, it handled a record 75.7 million passengers, a 1.0% increase from 2015. - An international airport is an airport that offers customs and immigration facilities for passengers travelling between countries. International airports are typically larger than domestic airports and often feature longer runways and facilities to accommodate the heavier aircraft commonly used for international and intercontinental travel. International airports often also host domestic flights. Some, such as Frankfurt Airport in Germany are very large; others such as Fa'a' International Airport in Tahiti, are quite small. - Colnbrook is a village in the unitary authority of Slough in Berkshire, England. It was formerly in the historic county of Buckinghamshire. It straddles the Colne Brook and Wraysbury River which join on its southwest border (two distributaries of the Colne). It is centred southeast of Slough, east of Windsor and west of central London. - The Middle Saxons or Middel Seaxe were a people whose territory later became, with somewhat contracted boundaries, the county of Middlesex, England. It included the early London settlement, and probably Surrey, the "south region" of the Middle Saxon territory. - Alluvium (from the Latin, "alluvius", from "alluere", "to wash against") is loose, unconsolidated (not cemented together into a solid rock) soil or sediments, which has been eroded, reshaped by water in some form, and redeposited in a non-marine setting. Alluvium is typically made up of a variety of materials, including fine particles of silt and clay and larger particles of sand and gravel. When this loose alluvial material is deposited or cemented into a lithological unit, or lithified, it is called an alluvial deposit. - The London Borough of Hillingdon is the westernmost borough in Greater London, England which had a population of 273,936 according to the 2011 Census. It was formed from the districts of Hayes and Harlington, Ruislip-Northwood, Uxbridge, and Yiewsley and West Drayton in the historic county of Middlesex. Today, Hillingdon is home to Heathrow Airport and Brunel University, and is the second largest of the 32 London boroughs by area. What is the relationship between 'heathrow ' and 'district'?
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