Why can't the women in the tunnel get into the tunnel?

The tunnel here refers to the hidden hole, that is, the hole directly made during excavation. Because the hidden cave is full of yin, women belong to yin, which aggravates the yin of the tunnel and brings bad luck to tunnel excavation. This is a custom handed down from the past and has been handed down to this day. Mainly a kind of "feudal thought", generally women are not allowed to enter the hole!