Photo by Kai Hagen Photography.

Construction of the Chesapeake and Ohio Canal began in 1828 in Georgetown, District of Columbia, and reached its terminus in Cumberland, Maryland, in the summer of 1850. The C&O Canal system included eleven stone aqueducts designed to carry the canal across the major river tributaries that drain into the Potomac River along the canal's route. Today, the C&O Canal is the most intact canal resource of the 36 major canals constructed in the United States between 1806 and 1850. The C&O Canal's chief engineer, Benjamin Wright, is considered by many as the father of American Civil Engineering. He was the lead engineer on the Erie Canal prior to engineering the C&O Canal.

The Monocacy Aqueduct is the largest of the eleven aqueducts erected along the C&O Canal, and is often described by many historians as one of the finest canal features in the United States. Ten of the eleven aqueducts remain as key features of the Chesapeake and Ohio Canal National Historical Park, which was designated as a National historical park in 1971. The Catoctin Aqueduct collapsed after its piers were gradually undercut and a flash flood took it down in 1972.

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