Hertfordshire

Hertfordshire (, ; often abbreviated Herts) is a ceremonial county in the East of England. It borders Bedfordshire to the north-west, Cambridgeshire to the north-east, Essex to the east, Greater London to the south and Buckinghamshire to the west. The largest settlement is Watford.

The county has an area of 634 square miles (1,640 km) and had an estimated population of 1,236,191 in 2024. Watford is in the south-west of the county, and its other settlements include Stevenage in the north, the city of St Albans in the centre, and Hemel Hempstead in the west. For local government purposes Hertfordshire is a non-metropolitan county with ten districts. Potters Bar in the south-east of the county was historically part of Middlesex.

Hertfordshire centres on the headwaters and upper valleys of the rivers Lea and the Colne; both flow south and each is accompanied by a canal. Elevations are higher in the north and west, reaching more than 800 feet (240 m) in the Chilterns near Tring. Hertfordshire's undeveloped land is mainly agricultural and much of the county is covered by the Metropolitan green belt.

Since 1903, Letchworth, in the far north, has served as the prototype garden city while Stevenage became the first town to expand under post-war Britain's New Towns Act 1946. Services have become the largest sector of the county's economy.