Given how fast ruins are covered by vegetation and dirt, how can something as simple as Nico Ditch (a 2-meter deep ditch) still be visible 1000 years after it was first dug?

Question

I came across this Wiki page: https://en.wikipedia.org/wiki/Nico_Ditch

The ditch was dug sometime between the 5th and 11th centuries. That’s 900-1500 years ago! There doesn’t seem to be any record of anyone maintaining it between now and then in any systematic way, so how is it still around? Shouldn’t it have filled in with dirt and vegetation by now?

In: Earth Science

Answer 1

The short answer is it has. The ditch would have been much more pronounced 1000 years ago. That you still see it today is a testament to how deep and wide it once was.

Edit to add after reading up on the wikipedia page there, apparently the ditch was used as a property boundary for many years after it outlived its usefulness as a defensive fortification. That would have lengthened its life and made it less likely to be backfilled, although it appears much of it has been anyway.