“But Salisbury Plain really is flat.”
I had always pictured it as flat when I was young. The terrain is a lot more rolling than I had expected.
https://www.visitwiltshire.co.uk/explore/salisbury-plain
https://www.gov.uk/government/news/reservists-train-on-salisbury-plain
The picture at the bottom is typical government workers: 2 working, 6 watching.
(Actually, to me it looks like training on how to extract a stuck vehicle.)