Billingsgate Market was said to be the oldest market in London, dating from at least the tenth century, but the wharf was by a Roman river wall so it may date from then. It became a fish market in the sixteenth century, and the quality of the language roared out there became legendary by the next century, so that both billingsgate and fishwife have become synonymous with highly robust and sustained profanity and abuse.
The market's original location was in the City of London, on the riverbank just east of London Bridge and next to the Custom House. It was moved slightly in 1850, from Lower Thames Street to a building on the nearby waterfront itself, and this was replaced by an arcaded market hall in 1876; but in January 1982 the market was finally closed down here, and re-established much downriver in the new developments of the Isle of Dogs, specifically on the north side of West India Docks, in Poplar.
The name probably comes from a person Billing, though fable would have it related to an ancient British king Belin or Belinus. An old variant form of the name, Blynesgate, suggests a different origin perhaps.
It was a general market, one of several in London confirmed by charter in 1327, and given the right to collect tolls in 1400. In 1699 an act confirmed its status as a free fish market, which it had been exclusively for many years. One exception to free trade was that only the Dutch has the right to sell eels: a way of thanking them for their support during the Great Fire of London in 1666.
The porters, in addition to their language, were also noted for their distinctive leather hats on which they balanced boxes of fish. These are now worn only on special occasions.
Home page: http://fis.com/billingsgate/