Jesus Lock.

Number 1 on the navigable part of the river Cam, going downstream and built in 1836. If you need to go through the lock these days, you have to do it yourself as there is no longer a lock keeper and his cottage is let out to students by the river conservation trust. As children we played around that area and we were allowed to help push the very heavy gates open and shut.  It was fun to watch the boats descend to the next river level as the water went down. Then to watch it rise again to the upper river level. Another happy memory jogged by a picture !