Clio Logo

The Lockkeeper’s House was built in 1835 and is listed on the National Register of Historic Places. It is not open to the public. This structure was built as a home for the lockkeeper of the extension that was built onto the Chesapeake and Ohio (C&O) Canal. Between 1833 and the Civil War, the canal allowed for the passage of freight along present-day Constitution Avenue. The canal was seldom used by 1870, and in the following decade, the city's engineers filled the canal with rock and soil. The historic home is now used for storage, and serves as a reminder of the historical importance of canals.


  • The Lockkeeper's House was built in 1835 at the eastern terminus of the C&O Canal
  • This plaque was added to the building in 1928, shortly before it was used as a public restroom

During the 1800s, the canal system crossing Washington, D.C. and running alongside the mall served to allow small cargo ships to travel between the Potomac and Anacostia Rivers. It was intended to connect Washington to national trade networks. Prior to the rise of railroads, it was a major thoroughfare for goods and people. The cargo included such materials as firewood and coal for fuel, food supplies, as well as marble and stone for public buildings.

In 1832, construction began on an extension that was built onto the Chesapeake and Ohio (C&O) Canal. Completed in 1833, this extension to the eastern terminus of the canal connected the Washington City Canal to the C&O via the Potomac River.

This stone structure, located at Constitution Avenue and 17th Street, once served as the residence of a lockkeeper and his family of thirteen children from 1835 to 1855. The lockkeeper was responsible for collecting tolls and operating the lock on the Washington City Canal. Additionally, he was managed the canal connections and kept records.

Nearby residents were often plagued with flooding caused by the canal overflows into the streets and the National Mall. By 1850s, the Washington City canal fell into disuse and became polluted. Unsanitary, costly, and prone to causing accidents, the canal was eventually closed to barge traffic. Twenty years following its closure, the city filled in the Canal and created Constitution Avenue, thus removing the need for a lockkeeper.

The lock keeper's house was abandoned in 1855, except for occasional habitation by squatters. It was partially renovated in 1903 and given to the U.S. government in the early 1900s. It has been used as Park Police headquarters (who used it to keep prisoners), public restrooms, and now storage.

A historical marker on the house includes the following inscription:

Formerly the eastern terminal of the Chesapeake and Ohio Canal. Erected about 1835. The canal passed along the present line of B Street in front of this house emptying into Tiber Creek and the Potomac River.1

1. "Lock Keeper's House Historical Marker." The Historical Marker Database. Accessed September 25, 2016. http://www.hmdb.org/marker.asp?marker=209. "Histories of the National Mall Why is There a Lockkeeper's House on the Mall?" Accessed September 25, 2016. http://mallhistory.org/explorations/show/lockkeepers-house. "Lockkeeper's House." NPS.gov Homepage (U.S. National Park Service). Accessed September 25, 2016. https://www.nps.gov/nr/travel/wash/dc34.htm.