Q: "Any chance of a picture of the Chester cord-rigg? I looked at where I thought they might be on a recent visit, but couldn't see anything ..."
A: I hope these images are of help. I have identified the location of the cord-riggs on the aerial shot and highlighted their profile on the general site shot.
Q: "How far apart are the ridges?"
A: Cord-riggs usually comprise of a series of narrow ridges less than a metre apart, formed as the result of cultivation and it is generally considered to date to the late pre-Roman Iron Age.