M25 motorway in the context of "Colnbrook"

The A1, also known as the Great North Road, is the longest numbered road in the United Kingdom, at 410 miles (660 km). It connects London, the capital of England, with Edinburgh, the capital of Scotland. The numbering system for A-roads, devised in the early 1920s, was based around patterns of roads radiating from two hubs at London and Edinburgh. The first number in the system, A1, was given to the most important part of that system: the road from London to Edinburgh, joining the two central points of the system and linking two of the UK's mainland capital cities. It passes through or near north London, Hatfield, Stevenage, Baldock, Biggleswade, Peterborough, Stamford, Grantham, Newark-on-Trent, Retford, Doncaster, Pontefract, York, Wetherby, Ripon, Darlington, Durham, Gateshead, Newcastle upon Tyne, Morpeth, Alnwick, Berwick-upon-Tweed, Dunbar, Haddington, Musselburgh, and east Edinburgh.

It was designated by the Ministry of Transport in 1921, and for much of its route it followed various branches of the historic Great North Road, the main deviation being between Boroughbridge and Darlington. The course of the A1 has changed where towns or villages have been bypassed, and where new alignments have taken a slightly different route. Between the North Circular Road in London and Morpeth in Northumberland, the road is a dual carriageway, several sections of which have been upgraded to motorway standard and designated A1(M). Between the M25 (near London) and the A720 (near Edinburgh) the road is part of the unsigned Euroroute E15 from Inverness to Algeciras.

A ring road (also known as circular road, beltline, beltway, circumferential (high)way, loop or orbital) is a road or a series of connected roads encircling a town, city or country. The most common purpose of a ring road is to assist in reducing traffic volumes in the urban centre, such as by offering an alternate route around the city for drivers who do not need to stop in the city core. Ring roads can also serve to connect suburbs to each other, allowing efficient travel between them.

Staines-upon-Thames, commonly known simply as Staines, is a market town in northwest Surrey, England, around 17 miles (28 kilometres) west of central London. It is in the Borough of Spelthorne, at the confluence of the River Thames and Colne. Historically part of Middlesex, the town was transferred to Surrey in 1965. Staines is close to Heathrow Airport and is linked to the national motorway network by the M25 and M3. The town is part of the Greater London Built-up Area.

The earliest evidence of human activity in the area is from the Paleolithic and, during the Neolithic, there was a causewayed enclosure on Staines Moor. The first bridge across the Thames at Staines is thought to have been built by the Romans and there was a settlement in the area around the modern High Street by the end of the 1st century CE. Throughout the Middle Ages, Staines was primarily an agricultural settlement and was held by Westminster Abbey. The first surviving record of a market is from 1218, but one may have taken place near St Mary's Church in the Anglo-Saxon period.

Spelthorne is a local government district with borough status in Surrey, England. Its council is based in Staines-upon-Thames; other settlements in the area include Ashford, Sunbury-on-Thames, Shepperton, Stanwell and Laleham. It is named after the medieval Spelthorne Hundred which had covered the area.

The borough is largely urban; although outside the boundaries of Greater London, it is almost entirely inside the M25 motorway which encircles London. The borough contains several large reservoirs, including the Wraysbury Reservoir, Staines Reservoirs and Queen Mary Reservoir, which all supply fresh water to London and surrounding areas.

The Borough of Dartford is a local government district with borough status in the north-west of the county of Kent, England. It is named after its main town of Dartford, where the council is based. Other notable settlements include Greenhithe, Stone and Swanscombe, along with an emerging new town at Ebbsfleet, and a number of smaller villages. It also includes Bluewater, one of the UK's largest shopping centres. The borough lies just outside the administrative boundary of Greater London, but a sizeable part of it lies within the M25 motorway which encircles London. Many of the borough's urban areas form part of the Greater London Built-up Area. The borough had a population of 116,800 at the 2021 census.

The neighbouring districts (clockwise from east) are Gravesham, Sevenoaks, the London Borough of Bexley and, to the north across the River Thames, Thurrock, to which it is linked by the Dartford Crossing.

Byfleet is a village in Surrey, England. It is located in the far east of the borough of Woking, around 1.5 miles (2.4 km) east of West Byfleet, from which it is separated by the M25 motorway and the Wey Navigation.

The village is of medieval origin. Its winding main street, High Road, contains old large public houses and several timber-framed houses, as well as other 16th and 17th century houses with listed status . The former Brooklands motor racing circuit is located just to the north, while to the east, across the River Wey, is the former Silvermere estate, now a golf club.

In London, the A40 forms a major trunk road starting in the City of London, and passing through six London Boroughs: Camden, Westminster, Kensington & Chelsea, Hammersmith & Fulham, Ealing and Hillingdon, to meet the M40 motorway junction 1 at Denham, Buckinghamshire. Outside London, the road then continues onwards to Fishguard, Wales.

The road has been re-routed several times in the last 100 years – part of the route of the London section of the A40 was laid out in the 1920s and 1930s when Western Avenue was built – now most of it is grade-separated, dual carriageway (divided highway). In the 1960s Westway was constructed, easing traffic access to and from the centre of the city. The A40 links the City of London and the West End to the M40 motorway and M25 motorway. The route is called The London to Fishguard Trunk Road (A40) in legal documents and acts.