The site that now contains the Pittsburgh Technology Center was originally occupied by the Pittsburgh and Boston Copper Smelting Works, later called C.G. Hussey and Company, in 1849 (Archeological Survey, 1989). Until the 1930s, there were still houses located along Second Avenue where the PTC is now located. The last company to have operations on the site was the Pittsburgh Works of the Jones and Laughlin Steel Corporation in 1979. This area was purchased by the Park Corporation in 1981, when J&L stopped their operations on the site. The Urban Redevelopment Authority of Pittsburgh (URA) then purchased the land from Park Corporation in 1983. The following is a list of other companies who have occupied the site in whole or in part before the Park Corporation purchased it. Many of these findings can be documented using Sanborn maps, which were maps created by the Sanborn Fire Insurance Company in order to record the facilities which they insured. Figures 1 through 5 are Sanborn maps of the facilities operated by these companies in the past on the PTC site.