The C&O Canal National Historic Park preserves almost 185 miles of the last remains of the Chesapeake & Ohio Canal along the Patomic River with most of the tow path restored as a trail.
Advertised as the world's smallest lift bridge those newfangled railroads had to have a way to avoid blocking commerce on the canal.
Nearby I photographed the Allegheny Poser Supply plant just because I liked the profile.
Here near Williamsport, Maryland is a lock and a large scum covered pool that allowed the boats to load, turn around, rest, or pass. The lock has been restored enough to have a new gate installed and the adjacent Lock Tenders House has also been restored. Neither rain, nor snow, nor dark of night; the lock tender did not get any time off although boats normally stopped at dark to rest the mules.
Nature of course always comes first so this aqueduct was completed in 1824 to allow the canal to pass over Conococheague Creek. In 1920 a canal boat bumped the upstream wall which plunged into the creek along with the boat. It was repaired with a wooden wall until a flood in 1924 finally closed the canal for good and it is now part of the trail.
A few miles upstream from Williamsport is a series of four locks in close proximity with this tunnel under the ruins for access to the main parking area and the Patomic River. Reflecting the number and importance of these locks the tenders house is more impressive and as I remember available for rental.
Looking right down the canal channel is lock 49 and 50 with the white painted mule shed in the background. The closeup is lock 48 and the longer range picture is lock 47. Obviously the park service is focused here on preserving rather than restoring like the lock No 1 in New Breman, Ohio where their major focus was creating a tourist attraction.
On the far right is a typical example of the trail with a packed gravel surface suitable for hiking or more rugged bike tires. The building in the ground was identified as a root cellar although I recall the identification being rather tentative since a thriving small community surrounded the locks and it could have been used for many purposes. Finally nestled among the tumbled side of a lock was my good friend the groundhog since he comes out on my birthday to tell you if more winter is a commin'.