Archaeologists are opening a system of secret caves and tunnels under the giant Pyramid of the Sun in Teotihuacan, Mexico. Little is known about the civilization that built Teotihuacan. The city had been long abandoned and overgrown when the Aztecs arrived in the Valley of Mexico. The tunnels were discovered in the 1970s during the installation of a light show for tourists. It was closed soon afterward. Most of the information about the tunnels was lost when Jorge Acosta, the archeologist who excavated them, died in 1976... probably from a curse!
Could anything in archaeology be cooler than finding a secret tunnel under a pyramid? You could drink on that story for the rest of your life.