From the Wikipedia page [1] The Steelyard, from the German Stalhof, was in the Middle Ages the main trading base of the Hanseatic League in London. It lay on the north bank of the Thames by the outflow of the Walbrook, in the Dowgate ward of the City of London. The site is now covered by Cannon Street station and commemorated in the name of Steelyard Passage. The Steelyard, like other Hansa stations, was a separate walled community with its own warehouses on the river, its own weighing house, church, counting houses and residential quarters. In 1988 remains of the former Hanseatic trading house, once the largest medieval trading complex in Britain, were uncovered by archaeologists during maintenance work on Cannon Street Station.