From an 1860 Pittsburgh directory. Weldin’s is still in the same place today, still selling papers and stationery. The address is now 415 Wood Street, but it is the numbers that have moved, not Weldin’s.
“Pittsburgh, at the junction of the Monongahela and Alleghany Rivers, is the second city in the State. It has a large trade and is noted for its commerce and its vast manufactures of iron. Alleghany City and Birmingham are connected with Pittsburgh by bridges.”
From A System of Modern Geography. The engraving may not be accurate down to the individual buildings, but it probably does a good job of conveying the general impression produced by the city just after the Civil War.