A Hill and a Ploughed Field

A featureless picture for a bland sort of a day. Dull and cold. I ran out of curved pins for assembling the quilt I'm working on, and had to drive over to Melrose to get some more.

TM wanted to investigate a structure he'd spotted in the distance, so off we   set up a muddy track. It turned out to be a viewing platform, and this is the view it commands. Luckily, there's a board to explain that this was once "a key defensive site and the hub of Roman roads in Scotland". 

The fort was called Trimontium - three hills. From here it looks like one, but there are another two peaks hidden behind it. This field was once a Roman military amphitheatre. How much effort must have gone into ploughing that to relative flatness?