I actually think this was done around the turn of the century(20Th

) or thereabouts, when this part of town was developed.
All the sidewalks were made of sandstone. This one is right at an intersection and is positioned in the corner of the lawn.
Nothing under the barrel!
We just thought it was wild to see it when we were cleaning up the property. In fact, we didn't even know the sidewalks were there until we scuffed some of the grass off the top of them. We figure it might be some indicator for sewer pipes or other underground objects or a measuring point when the street was laid out.
Trout, I LMAO when I read the Cana-by God-da. That is way cool! 8)
Oh, by the way, I lived in Canada back in the early 60's. my brother was born there. We were at Goose Bay, Labrador. What a place! I loved it, but I was just a kid. Halloween night we had 6 feet of standing snow on the ground. 8)
Good luck! HH