Hump district reconstruction progress, Sixth Avenue at Wylie Avenue looking to Webster Avenue, showing raised sidewalks. The "hump" cut took place in the area of Downtown known as Grant's Hill. The project began in planning in 1909 and ended with the final cut in 1913. It changed the gradient of Grant Street, Diamond Street, and Oliver, Fifth, Sixth, Webster and Wylie Avenues. Please see, Frederick Law Olmstead, Pittsburgh Main Thoroughfares and the Down Town District: http://digital.library.pitt.edu/cgi-bin/t/text/text-idx?c=pitttext&view=toc&idno=00aep1324m for more information.
