The photograph looks across the Seneca Aqueduct (also known as Aqueduct No. 1) from within the drained channel of the Chesapeake & Ohio Canal. The water of Seneca Creek is visible in the foreground with the unused channel extending towards the background. Built by the contractors Holdsworth and Isherwood for a total cost of $24,340.25, the aqueduct was the first of eleven intended for the canal. It was built between October 1828 and April 1832 of red sandstone mined from the neighboring Seneca Quarry. Three identical 34-foot arches supported the aqueduct over Seneca Creek. At the downstream end, it connects directly to Lock 24.
The blueprints below show the initial design as well plans for the repair of the aqueduct following the collapse of an arch in flooding on September 12, 1971. In 1980 the aqueduct was stabilized with steel beams and pipes but the destroyed arch has not been rebuilt.