English: Lock 29 (Lander) on the C and O Canal. The NPS site (http://www.hscl.cr.nps.gov/insidenps/report.asp?STATE=&PARK=CHOH&STRUCTURE=&SORT=&RECORDNO=319) states: Lock 29 is constructed out of 2/3 granite and 1/3 flint stone. It is constructed to standard dimensions with a 7' lift. It was one the first few locks to be extended in order to raise or lower two barges at a time. It had an extension added to the upper end in the early 1870s. The brest wall on the upper end of the upper lock gate pockets and upper extension walls were removed. The bottom is excavated about 8' for the 100' continuation of the lock and the extension of the lock walls was made by a rock filled wood cribbage. A new drop gate was placed in the upper end of a new upper lock gate locket. There is a noticeable tilt in several sections of the berm side lock wall with clear width of lock varying from 14' to 14'-3". The lock extension is only piles of rock and both gates are gone. Note: On the C&O they called the watercraft "boats" instead of "barges".