Tring is a market town and civil parish in the Borough of Dacorum, Hertfordshire, England. It is situated in a gap passing through the Chiltern Hills, classed as an Area of Outstanding Natural Beauty, 30 miles (48 km) from Central London. Tring is linked to London by the Roman road of Akeman Street, by the modern A41 road, by the Grand Union Canal and by the West Coast Main Line to London Euston. Settlements in Tring date back to prehistoric times and it was mentioned in the Domesday Book; the town received its market charter in 1315. Tring is now largely a commuter town within the London commuter belt. As of 2013, Tring has a population of 11,731.

The name Tring is believed to derive from the Old English Tredunga or Trehangr. Tre', meaning 'tree' and with the suffix 'ing' implying 'a slope where trees grow'.

There is evidence of prehistoric settlement with Iron Age barrows and defensive embankments adjacent to The Ridgeway, and also later Saxon burials. The town straddles the Roman road called AkemanStreet, running through as the High Street. Tring was the dominant settlement in the area, being the primary settlement in the Hundred of Tring at the time of the Domesday Book (1086). Tring had a large population and paid a large amount of tax relative to most settlements listed in that survey. Landholdings included the manor of Treunga, assigned to Count Eustace II of Boulogne by William the Conqueror.

In 1315 the town was granted a market charter by Edward II. This charter gave Faversham Abbey the right to hold weekly markets on Tuesdays, and a ten-day fair starting on 29 June, the Feast of Saints Peter and Paul. It also prevented the creation of any rival markets within a day's travel of the town. The tower of the Church of St Peter and St Paul was built somewhere in between 1360 and 1400.

Until 1440, there was a small village east of Tring called Pendley (or Penley, Pendele, or Pentlai). The landowner Sir Robert Whittingham received a grant of free warren from King Henry VI. He enclosed 200 acres (about 80 hectares) and tore down the buildings on the land, returning the estate to pasture, and built a manor house, Pendley Manor. This house was variously inhabited by the Verney, Anderson and Harcourt families until the mid-19th century.

Tring Park Mansion was designed by Sir Christopher Wren and was built in 1682 for the owner Henry Guy, Gentleman of the Privy Chamber to Charles II. John Washington, the son of the Reverend Lawrence Washington and Amphyllis Twigden, was born and brought up in Tring. In 1656 he left Tring to go on a trading voyage to Virginia, but after a shipwreck on the Potomac River he remained in Virginia, married and started a family which eventually included his great-grandson, George Washington, the first President of the United States. The town's prosperity was greatly improved at the start of the 19th century by the construction nearby of the Grand Junction Canal, and soon afterwards in 1835 the London and Birmingham Railway. Industries which benefited included flour milling, brewing, silk weaving, lace-making and straw plaiting.

In 1835, the medieval Pendley Manor was destroyed by fire. A local landowner, Joseph Grout Williams, commissioned a new manor house to be built in Jacobean Revival style, and this building still stands today on Station Road.

In 1836 Thomas Butcher, a wholesale seed and corn merchant, and his son also called Thomas, established a private bank, Thomas Butcher & Son in Tring High Street. The business was subsequently run by Thomas's grandsons, Frederick and George, and was also known locally as Tring Old Bank. By 1900 it had branches in Aylesbury, Chesham and Berkhamsted. From this time it became the subject of successive bank consolidations, eventually becoming a branch of the National Westminster Bank, the last to be represented in the town.

In the late 19th century the estate became the home of the Rothschild family, whose influence on the town was considerable. Nathan Mayer Rothschild's son Lionel Walter Rothschild (2nd Lord Rothschild, 1868-1937) built a private zoological museum in Tring. This housed perhaps the largest collection of stuffed animals worldwide. As the Natural History Museum at Tring, it has been part of the Natural History Museum, London since 1937. In April 2007 the museum changed its name to the Natural History Museum at Tring in order to make people more aware of the museum's link to London's Natural History Museum. In 1902 the 2nd Lord Rothschild also released the edible dormouse (Glis glis) into Tring Park. He used to ride around the town in a carriage drawn by zebras. In the town centre of Tring there is a pavement maze in the shape of a Zebra's head in order to remember the link that Tring has to the Rothschild family.

The former livestock market in Tring, redeveloped in 2005, was believed to be the last remaining example of its type in the UK. It is now the home of a weekly Friday market and a fortnightly Saturday farmers' market. Some of the former livestock pens have been retained. The old livestock market office is now the home of the Tring Local History Museum, which opened in September 2010.

In 2008 Tring became a Transition Town with the support of Tring Town Council.

Heygates Mill is a flour mill. Originally it was a windmill, and the company was run by William Mead. The windmill was demolished in 1910 to make way for a wheat storage silo. In those days, Mead lived on-site, in a house next to the yard, and owned half the area taken by the mill of today. The remaining space was occupied by boat-builders, Bushell Brothers, who built narrowboats for the canal. The Heygate family took over Mead's business in 1945, and today mills 100,000 tons of wheat a year, resulting in 76,000 tons of flour. This is mainly bakers' flour, but there is also a commitment to wholemeal digestive for biscuits, bulk outlets and a large output of 1.5 kg bags from the pre-packed flour plant.

In the days of the Tring windmill, only two men operated the system, milling ten stone per hour. Now, computerised, more than twelve tons per hour are produced. Heygate's Tring mill has 80 employees and sixteen trucks delivering throughout the south of England.