File:Lock 69 C and O Canal from NPS.jpg

English: Lock 69. NPS site says: Lock 69 is the 11th of the 13 composite locks. These locks differ from the other locks on the canal. Between the upper end of the lower gate pockets to the lower end of the upper gate pockets the stone walls were moved 9 ¼° on each side, resulting in a clear dimension between lock walls of 16’-16 ½” rather that the 15’ previously adhered to. The normal clear dimension was resumed both up and down from these points. The walls were of rough-cut and rough-coursed limestone, principally dry-laid where the walls were widened and mortared in the other areas. The wider area was filled in with 5 ¼” square timbers. This wooden section of the lock was “water-proofed” at first by being “kyanized” and later with creosote. Lock 69 is located a quarter of a mile below Lock #70, and two-thirds of a mile above Lock #68. The area is a fourth of a mile from the village of Oldtown, and early Maryland settlement. Start of work on the lock began in 1848 and it was finished in 1850. The wood lining of the lock was totally replaced with concrete after 1900, including the coping and much of the upper and lower extension and wingwalls. Protruding existing bolts on the towpath side indicate an added heavy wood timber to the top of the wall, probably as a tow line, but no wood remains. The lower concrete-covered lock gate pockets are 22" deep rather than the normal 16," one of the few instances in variance of this dimension. The upper lock gates remain, the towpath gate is in place, and the berm is fallen in. Much of the gate hardware is in place, although not of the original type. The wall are not nearly as plumb in the original 15' clear width is slight. The lock has been dammed with concrete at the upper ened of the upper extension wall.