Lockhouse 21

Lockhouse 21, locally known as “Swains” after the family who lived there for over a century, is the newest lockhouse to join the Canal Quarters program. Opened in July 2019, this lockhouse has been completely modernized and is ADA-accessible with a bathroom and Murphy bed on the first floor, ramps into the house, and hallways wide enough to accommodate a wheelchair.

The house interprets 1916, the year the National Park Service was formed and the date when the C&O Canal was beginning to transition from a working canal to a recreational space. Unique period furnishings transport visitors to the early twentieth century, and scrapbooks tell stories of a time when Woodrow Wilson was President, the United States had not yet entered World War I, and the women’s and civil rights movements were gathering steam.

Lockhouse 21 features accessible parking, accessible ramps to the front door and within the first floor of the building (upon request during booking), accessible bathroom, kitchen, and picnic area facilities, and single-sized Murphy bed located on the first floor. The second floor is only accessible via stairs. The lockhouse sits beside a parking lot and is not as secluded as the other lockhouses, but is the most recently rehabilitated.

>> Learn more about the rehabilitation of Swains Lockhouse here

>> View photos of the rehabilitation here

>> WTOP’s feature on Swains Lockhouse

*Effective May 31, 2024, the C&O Canal Trust will increase regular maintenance and administrative fees for some of the lockhouses to cover increased maintenance and program costs. These one-time fees for Lockhouses 6, 10, and 21 will increase from $20 to $80 per reservation, and for Lockhouse 49 will increase from $10 to $65. This change will not affect any reservations made before May 31, 2024 or any reservations at the rustic lockhouses (22, 25, 28). All reservations, fees, and donations made to the Canal Quarters program contribute directly to program support and expansion as well as the preservation of these historic buildings. We thank you for your understanding and continued support of the Canal Quarters interpretive program in the C&O Canal National Historical Park.*


Towpath Mile: 16.7
Parking: Available
Price Per Night: $160
Additional Fees: One-time $20 maintenance fee; One-time $20 occupancy fee for groups of 6-8 only
Time Period Depicted: 1916
Nearest Communities: Potomac

Book Now Gift Certificates

Features & Amenities

  • 1910s kitchen with stove, oven and refrigerator
  • 1910s bathroom with tub/shower
  • One bedroom with full sized bed and a trundle; One bedroom with 2 twins and 2 trundles; and an ADA-accessible Murphy bed on first floor
  • Central AC/heat
  • Fire Ring
  • Easy access to the Capital Beltway
  • Linens and pillows not provided
  • Fireplaces are NOT functional


Lockhouse 21
10700 Swains Lock Rd
Potomac, MD 20854
Click here for directions and a map.

Check-In: 3:00 p.m.

Check-Out: 10:00 a.m.

“The whole C&O Canal trip is wonderful and staying in a Canal Quarters [Lockhouse gives] you a better sense of the times when it was operational. It was also a welcome relief to get off the bikes and into a warm house.” – Canal Quarters Guest

“We took advantage of the accessibility features and found them to be so well-considered and implemented—the first floor of the house was totally accessible to my spouse, who uses a power chair. Thank you so much! Great location, of course, and perfect, close, getaway spot.” – Canal Quarters Guest