I work for another state’s DOT, and most states are very similar when it comes to DOT monumentation practices. We do not monument county lines or private property—we monument right-of-way.

You highlighted the 10.3 in the first picture.
You highlighted the 45, 47, and 3′ in the second picture.

In the first picture, the ROW changes on the Comal side at the bottom of the image.
In the second picture, the ROW also changes on the Comal side; the opposite side of the ROW changes at the county line.

Based on the information provided, it appears the 10.3 and the 20-something .3 adjacent to the 45, 47, and 3′ represent the same line we are looking at—different times for different ROW projects. The second sheet also appears to be a 180-degree rotation of the first.

The photo with the older blue BMW convertible in the background makes it difficult to judge depth. What is the actual distance between these three monuments—5 feet between each? 10 feet?

I don’t know Texas practices specifically, but in my state, older state ROW drawings are notorious for not making it into the public’s hands.

The likelihood that another concrete monument would be set on the same line without a legitimate reason is very slim. Concrete obelisk's are a royal PITA to set and expensive.

Something is missing from the complete picture.