Coordinates: 51°28′35″N 0°10′05″E / 51.4763°N 0.1681°E / 51.4763; 0.1681

Erith ⁱ/ˈɪərɨθ/ is a district of southeast London on the River Thames. Erith's town centre has undergone a series of modernisations since 1961. Erith is geographically an outer lying area of London, although it is can be seen as having many of the characteristics of the Inner city, namely most residences consisting largely of flats and council blocks, with fewer houses, and shops and other commercial properties interspersed between.

Work at the former British Gypsum site in Church Manorway by the Museum of London Archaeological Service showed that the area had a dense forest of oak, yew and alder during the Neolithic Period, which by the Bronze Age had given way in part to sedge fen.

Their work at the former site of Erith School in Belmont Road revealed the presence of prehistoric settlement, and of a substantial settlement or farmstead dating from the first century.

Following the collapse of Roman rule at the beginning of the 5th Century, Britain was colonised by invaders from northern Europe called the Anglo-Saxons. The Anglo-Saxon Chronicle tells us that they won the Battle of Crayford in 457, slaying many men in the process, and shortly after claimed the whole of Kent. Their different way of life was reflected in their pattern of settlement. The town and country estates of the Roman bureaucrats gave way to a network of villages, occupied by warriors and farmers. Erith was one of these villages, and has a Saxon name, thought to have been derived from a word meaning `muddy harbour' or `gravelly landing place'. There was probably a church on the site of the present St John the Baptist church during Roman times and almost certainly a Saxon building. The early settlement was based around this church, meaning that the centre of Erith was once west of its current location.