Potters Bar is a town in Hertfordshire, England, just north of London. It has a population of about 20,000. The town started life in the early 13th century and remained more or less unchanged until the arrival of the railway in the 1850s. It was originally part of Middlesex but was ceded to Hertfordshire in 1965 when most of the rest of Middlesex was subsumed into Greater London.

The origin of the Potters component of the town's name is uncertain but is generally thought to have been derived from evidence of a Roman pottery that was thought to have been sited locally, or from the family Pottere who lived in the South Mimms parish. The Bar component is thought to refer to the gates leading from the South Mimms parish and into the Enfield Chase parish, or possibly from some sort of toll on the Great North Road. The original "Bar" is said to have been at what is now the Green Man pub, or at the current entrance to Movern House.

Darkes Lane, Potters Bar. Looking towards the railway bridge

The Great North Road, the original main road route from London to the north of England and ending at Edinburgh in Scotland, passed through Potters Bar High Street - originally numbered as the A1, later the A1000. The A1 was built as a major (what was then called "arterial") road, and a crossroads at Bignells Corner linked the Barnet - St Albans Road with the A1. Potters Bar is now also served by junction 24 of the M25.

Potters Bar station is the highest on the railway line between London's Kings Cross station and York, and the town's name entered national headlines as the site of a rail crash that killed 7 people and injured 76 on May 10, 2002.