That’s amazing, I had no idea.
It’s huge. I recall (probably a different documentary, I think I have it on DVD around here somewhere) how one of the corridors had a slope or steps down, and another storey had been added, then a right turn led to an unfinished passage that never had to be (or was unable to be) completed.
OTOH, the largest single room known in the KV is that of Ramses II himself; probably once filled to the ceiling with wealth, it had been plundered in antiquity.
https://thebanmappingproject.com/tombs/kv-07-rameses-ii