The Matrix

I just spent a whole day trying to work out the way the graves intercut each other. Not helped by some of the diggers not having recorded the information. How could they think it was helpful to write "This grave has been truncated by another grave" without indicating which????!!!!
Sorry; that was a bit of an idiosyncratic complaint. I don't imagine that many people will feel my pain! :P
There are another two matrices about as big as this, also covered with long wandering arrows and question marks...