Leaving the Depot at the head of Pratt street, the road passes by a high and extensive embankment over the ravine of Carroll's branch and enters the cut in Carroll's woods at the end of the first mile; thence by a short but lofty embankment and bridge of stone of 20 feet span, over Gwynn's run; and soon after it crosses Gwynn's Falls by the splendid structure, called, in honor of Carroll of Carrollton, the Carollton Viaduct. This bridge rises from the surface of the water about 65 feet, and is upwards of three hundred feet in length. The principal arch is 80 1/4 feet span, and its versed sine is 30 feet. Besides this, there is a smaller arch of 20 feet span, used as a road way. The stone work is dressed, and is composed of the Patapsco granite. The total cost was $53,061 75.
Excerpted from John H.B. Latrobe, Jr., Picture of Baltimore (Baltimore, MD: Lucas Fielding, Jr., 1832), 203.