Meat has been traded at Smithfield Market for more than 800 years, making it one of the oldest markets in London. The livestock market expanded over the centuries to meet the demands of the growing population of the City. The present Smithfield Meat Market on Charterhouse Street was established by an Act of Parliament: the 1860 Metropolitan Meat and Poultry Market Act. The buildings stand on top of a curious warren of tunnels: previously, live animals were brought to the market on the hoof and were slaughtered on site, these are now used for storage and as basements. Smithfield is the only great London market not to have moved out of Central London.