101. Alexandria Aqueduct

Look out over the Potomac. To your left stands the Key Bridge.
Close to the Virginia side, a little to the right, you see in the river the last remaining pier of the old Alexandria Aqueduct, sometimes called the Potomac Aqueduct. And directly in front of you stands its black stone abutment.
The Alexandria Canal Company envisioned that the Potomac Aqueduct would carry - 30 feet above the river - boats loaded with goods coming from the Potomac valley, destined to the port of Alexandria. In fact, an editorial in the Alexandria Gazette from 1843 said, "We regard the aqueduct as the opening of new and brighter prospects of success and prosperity." Aspirations were high.
But the aqueduct and its wooden superstructure always seemed to need repairs. Tolls declined. By May of 1859, the treasury of the Alexandria Canal Company consisted of exactly 48 cents.
Things went from bad to worse. The Civil War came. Steam power and tugboats, too. There was a major breach in the aqueduct. In 1886, the government took it over, tore down the wooden structure and built an iron truss bridge over the piers for wagons, carriages, trolleys, and later, the automobile.
That lasted a while. In the 1920's, they built the Key Bridge and a decade later, the aqueduct over the Potomac was demolished.
The other piers in the river remained until 1962 when they were deemed a hazard to navigation. The irony is that Francis Scott Key never wanted the Potomac Aqueduct here in the first place. He said the same thing: it was a hazard to navigation. And now the Key Bridge is named after him.
The Potomac or Alexandria Aqueduct went through many phases, and there's not much left now. People tend to walk right by. But this aqueduct was certainly a grand and magnificent achievement for its time.

For more information on the Aqueduct and surrounding area, please click here:

http://www.canaltrust.org/discoveryarea/alexandria-aqueduct/