Staines-upon-Thames, commonly known simply as Staines, is a market town in northwest Surrey, England, around 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.

The industrialisation of Staines began in the mid-17th century when Thomas Ashby established a brewery in the town. Improvements to the local transport network in the mid-19th century also stimulated an expansion of the local population. The current Staines Bridge, designed by George Rennie, was opened in 1832 by William IV and the first railway line through Staines opened in 1848. The town became a centre for linoleum manufacture in 1864, when Frederick Walton established a factory on the site of the 13th-century Hale Mill.

At the end of the 20th century, Staines became infamous as the home town of the fictional film and television character, Ali G. Although many local residents felt that the town's reputation was suffering through its association with the character, Sacha Baron Cohen, the creator of Ali G, praised Staines for being a "lovely, leafy, middle-class suburb... where swans swim under the beautiful bridge". Partly in response to the reaction to the character, Spelthorne Borough Council voted in 2011 to add the suffix "upon-Thames" to the official name of the town.

Toponymy

The earliest document to refer to Staines is the Antonine Itinerary, thought to have been written in the early 3rd century AD, in which the location appears as Pontibus, meaning "at the bridges". The first surviving records of Staines from the post-Roman period are from 1066, when the settlement appears in two separate charters as Stana and Stane. The Royal Mail adopted the new name in mid-2013. It is close to the borders of Berkshire and Greater London. The town is linked to junction 13 of the M25 by the A30 and to the M3 by the A308. The area surrounding the borough council offices and the magistrates' courts, to the southeast of the town centre, is known as Knowle Green.