The London Metropolitan Archives is the principal local government archive repository for the Greater London area, including the City of London: it is the largest county record office in the United Kingdom. It was established under its present name in 1997, having previously been known as the Greater London Record Office. It is administered and financed by the City of London Corporation.
The archive is based at 40 Northampton Road, Clerkenwell, London. It attracts over 30,000 visitors a year and deals with a similar number of written enquiries. LMA's extensive holdings amount to over 72 miles of records of local, regional and national importance. With the earliest record dating from 1067, the archive charts the development of the capital into a modern-day major world city.
Wikipedia https://en.wikipedia.org/wiki/London_Metropolitan_Archives
Coordinates 51°31'29.859" N -0°6'28.396" E