In the 16th century, blacksmiths and other workshops occupied the space between the cathedral, the Lion's Gate (Puerta del León), and the Royal Alcázar's inner walls. In the early 17th century, the area was chosen to be the site of the great Merchants' Exchange, or Casa Lonja de Mercaderes. The exchange building would later become the General Archive of the Indies, or Archivo General de Indias, housing most of the historical documents relating to the first circumnavigation of the world.