Aldgate was the eastern-most gateway through the London Wall leading from the City of London to Whitechapel and the East End of London.
The etymology of the name "Aldgate" is disputed. It is first recorded in 1052 as Æst geat but had become Alegate by 1108. Writing in the 16th century, John Stow derived the name from "Old Gate" .
It is thought that a gate at Aldgate spanned the road to Colchester in the Roman period, when London Wall was constructed. The gateway – which probably had two circular towers – stood at the corner of the modern Duke's Place, on the east side of the City, with a busy thoroughfare passing through it.
The City ward of Aldgate is bounded on the east by the line of the former London Wall, effectively parallel with Houndsditch, which separates it from the Portsoken ward; it is bounded on the south by Tower ward and on the west and north by the Langbourn, Lime Street, and Bishopsgate wards.