These are some physical references of hell. Jesus decended to hell after his death on the cross/torture tree. The following are from the JW bible.
NWT - EPH ch4 vs 9 Now the expression “he ascended,” what does it mean but that he also descended into the lower regions, that is, the earth? 10 The very one that descended is also the one that ascended far above all the heavens, that he might give fullness to all things
N WT - MATH ch12- vs 40 For just as Jo´nah was in the belly of the huge fish three days and three nights, so the Son of man will be in the heart of the earth three days and three nights.
respectfully,
DC