Locks on the C&O Canal

Swain's Lock

The Locks on the C&O Canal, located in Maryland, West Virginia, and Washington, D.C. of the United States, were numbered from 1 to 75 with two locks, 63⅓ and 64⅔, having fractional numbers and no lock 65. There is also a lock at the downstream end of the canal in Washington, DC where Rock Creek flows into the Potomac River which is sometimes called Lock 0 or the Tidewater Lock.

Some of the locks were also informally named, usually after a prominent lockkeeper, a nearby town or important geographical feature. Some locks are known by more than one name and some are only known by their number.

With respect to the fractional locks, it was found that the level of the canal between locks 62 and 66 could be raised in three steps instead of four. So the additional locks through there were numbered 1⅓ steps apart (62, 63⅓, 64⅔ and 66) so that the other locks on the canal did not have to be renumbered.

Map of the path of the C&O Canal.

Lock	Miles	Name	Nearby landmarks	Coordinates
0	0.0	Tidewater Lock		38.900°N 77.058°W / 38.900; -77.058
1	0.38		Georgetown	38.904°N 77.058°W / 38.904; -77.058
2	0.42		Georgetown	38.904°N 77.059°W / 38.904; -77.059
3	0.49		Georgetown	38.904°N 77.059°W / 38.904; -77.059
4	0.54		Georgetown	38.904°N 77.061°W / 38.904; -77.061
5	5.0	Brookmont Lock	Brookmont	38.940°N 77.122°W / 38.940; -77.122
6	5.4	Magazine Lock	Little Falls	38.945°N 77.124°W / 38.945; -77.124
7	7.0	Chataqua Lock	Glen Echo	38.965°N 77.139°W / 38.965; -77.139
8	8.33	Seven Locks 1		38.971°N 77.161°W / 38.971; -77.161
9	8.7	Seven Locks 2		38.972°N 77.167°W / 38.972; -77.167
10	8.79	Seven Locks 3		38.972°N 77.169°W / 38.972; -77.169
11	8.97	Seven Locks 4		38.972°N 77.172°W / 38.972; -77.172
12	9.29	Seven Locks 5		38.972°N 77.178°W / 38.972; -77.178
13	9.37	Seven Locks 6	American Legion (Cabin John) Bridge	38.972°N 77.179°W / 38.972; -77.179
14	9.47	Seven Locks 7		38.972°N 77.181°W / 38.972; -77.181
15	13.45	Six Locks 1	Great Falls	38.989°N 77.244°W / 38.989; -77.244
16	13.60	Six Locks 2	Great Falls	38.992°N 77.245°W / 38.992; -77.245
17	13.99	Six Locks 3	Great Falls	38.996°N 77.248°W / 38.996; -77.248
18	13.99	Six Locks 4	Great Falls	38.998°N 77.249°W / 38.998; -77.249
19	14.17	Six Locks 5	Great Falls	38.999°N 77.248°W / 38.999; -77.248
20	14.30	Six Locks 6 - aka Tavern Lock	Great Falls Tavern	39.000°N 77.248°W / 39.000; -77.248
21	16.64	Swain's Lock		39.032°N 77.244°W / 39.032; -77.244
22	19.63	Pennyfield Lock		39.054°N 77.289°W / 39.054; -77.289
23	22.12	Violette's Lock and Inlet Lock 2		39.067°N 77.329°W / 39.067; -77.329
24	23.00	Riley's Lock	Seneca Creek Aqueduct	39.069°N 77.340°W / 39.069; -77.340
25	30.8	Edward's Ferry	Poolesville	39.103°N 77.472°W / 39.103; -77.472
26	39.4	Wood's Lock		39.216°N 77.458°W / 39.216; -77.458
27	41.5	Spinks Ferry	Monocacy Aqueduct	39.191°N 77.471°W / 39.191; -77.471
28	48.9	Fulton's Lock	Point of Rocks	39.282°N 77.548°W / 39.282; -77.548
29	50.89	Lander Lock or Catoctin Lock		39.307°N 77.559°W / 39.307; -77.559
30	55.0		Brunswick, Maryland	39.311°N 77.630°W / 39.311; -77.630
31	58.0	Weverton Lock		39.329°N 77.681°W / 39.329; -77.681
32	60.23		Sandy Hook, Maryland	39.324°N 77.719°W / 39.324; -77.719
33	60.7		Harper's Ferry	39.325°N 77.727°W / 39.325; -77.727
34	61.57	Goodheart's Lock	Harper's Ferry	39.333°N 77.739°W / 39.333; -77.739
35	62.33		Harper's Ferry	39.337°N 77.751°W / 39.337; -77.751
36	62.44		Harper's Ferry	39.337°N 77.753°W / 39.337; -77.753
37	66.96	Mountain Lock		39.385°N 77.735°W / 39.385; -77.735
38	72.65	Shepherdstown Lock	Shepherdstown, West Virginia	39.435°N 77.798°W / 39.435; -77.798
39	74.0	One Mile Lock	James Rumsey Bridge, Snyder's Landing	39.446°N 77.783°W / 39.446; -77.783
40	79.41		Horseshoe Bend	39.486°N 77.779°W / 39.486; -77.779
41	88.9			39.533°N 77.838°W / 39.533; -77.838
42	89.04			39.532°N 77.840°W / 39.532; -77.840
43	92.96			39.542°N 77.866°W / 39.542; -77.866
44	99.3	Williamsport	Williamsport, Maryland	39.594°N 77.825°W / 39.594; -77.825
45	107.27	Two Locks 1		39.614°N 77.926°W / 39.614; -77.926
46	107.42	Two Locks 2		39.616°N 77.927°W / 39.616; -77.927
47	108.8	Four Locks 1		39.617°N 77.947°W / 39.617; -77.947
48	108.8	Four Locks 2		39.616°N 77.948°W / 39.616; -77.948
49	108.8	Four Locks 3		39.615°N 77.949°W / 39.615; -77.949
50	108.8	Four Locks 4		39.614°N 77.949°W / 39.614; -77.949
51	122.59	Hancock 1	Hancock, Maryland	39.693°N 78.151°W / 39.693; -78.151
52	122.85	Hancock 2	Hancock, Maryland	39.694°N 78.156°W / 39.694; -78.156
53	130.0	Irishman's Lock	Leopard's Mill	39.651°N 78.241°W / 39.651; -78.241
54	134.0			39.624°N 78.289°W / 39.624; -78.289
55	134.0		Near Dam 6	39.625°N 78.292°W / 39.625; -78.292
56	136.2	Sideling Lock	Sideling Hill	39.637°N 78.329°W / 39.637; -78.329
57	139.2			39.627°N 78.361°W / 39.627; -78.361
58	143.9			39.621°N 78.406°W / 39.621; -78.406
59	146.6			39.611°N 78.433°W / 39.611; -78.433
60	149.7		Stickpile Hill	39.582°N 78.404°W / 39.582; -78.404
61	153.1			39.584°N 78.460°W / 39.584; -78.460
62	154.2			39.571°N 78.453°W / 39.571; -78.453
63⅓	154.5		Paw Paw Tunnel	39.567°N 78.454°W / 39.567; -78.454
64⅔	154.6			39.566°N 78.455°W / 39.566; -78.455
66	154.7			39.565°N 78.457°W / 39.565; -78.457
67	161.8	Darkey's Lock		39.525°N 78.533°W / 39.525; -78.533
68	164.8	Crabtree's Lock		39.530°N 78.589°W / 39.530; -78.589
69	166.4	Twigg's Lock		39.540°N 78.608°W / 39.540; -78.608
70	166.7	Oldtown		39.540°N 78.612°W / 39.540; -78.612
71	167.0			39.541°N 78.618°W / 39.541; -78.618
72	174.4	The Narrows or Ten Mile Lock		39.575°N 78.730°W / 39.575; -78.730
73	175.4	North Branch 1		39.588°N 78.736°W / 39.588; -78.736
74	175.5	North Branch 2		39.588°N 78.738°W / 39.588; -78.738
75	175.6	North Branch 3		39.587°N 78.741°W / 39.587; -78.741
	184.5	End of the canal	Cumberland, Maryland	39.649°N 78.763°W / 39.649; -78.763

See also

• Canal Place, Cumberland

External links

• A Virtual Tour of the C&O Canal
• GPS Landmark Coordinates along the C&O Canal