Tickets 40, online group can be slightly cheaper, 65 years old and older are free of charge. There is a paid parking lot at the door, 5 yuan a time. There are crowds of people, just give an explanation. First visit the exhibition hall of the three countries, and it is good to increase knowledge. The underground transport road is a one-way line, just follow. More than 8,000 meters have been explored and more than 700 meters have been opened. It is breathtaking that ancients more than 1800 years ago could build such a large-scale tunnel underground.