In your opinion, is this correct? (Details inside)

I recently read that the forts along Hadrians wall were placed at 14 mile intervals because that was a half days march.
Is that right?
Not the locations of the forts but that 14 miles was a half day march? I know they were on a good roadbed but they would also be in full armor, with weapons and probably a pack as well.
But then again walking was the normal way for the vast majority to get around then so I assume they had been doing it since they were small.
But even so, isn’t 28 miles an impressive distance to cover in a day.