Truth about underworld

You have always heard people speaking about others visiting the underworld,I had a conversation with one lady who once found herself in the underworld.she said there is an entrance to the underwater and to my surprise its just a place where there is free air and all the activities going on on Earth goes on there, there are factories .and even companies and indeed a very busy area full of all riches,the technology over there is of high standard....to be continued.