Underground Electricity Energy in Geneva

Today we were visiting underground Electricity Energy in Geneva; it is Enormous place big underground space. I was completely impressed from this place.
First time I visited this kind of place before I have not the opportunity to see this underground Electricity Energy. The underground Electricity Energy established in 1990 and the electricity is supplying in center of Geneva and the electricity volts are 130,000 to 18,000 volts. It is really wonderful experience for me to visit all that.