• If you look it's also in the course 2 above as well, and I suspect behind the roadsign.

    I'd guess that it's something to do with the exact length that the wall needed to be. As it's by the street sign, that might suggest that it's towards the end of the wall, and the builder knew that unless that was done, the wall would be half a brick too long.

About

Avatar for MrDrem @MrDrem started