Ok the round step structure in the wall, this is isn't the only house I've seen with it, what was it?
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@sheseala
That's a couple of possible things.
most likely: There was a planned weight load at that spot, like a chimney, and they wanted strength to prevent bowing out or slippage at the bottom of the foundation wall from the pressure.
Another possibility, a Piece of "Ledge" (common in the East U.S.) that it just wasn't worth dynamiting to get rid of, so they just bricked around it.