816 Project, the world's largest man-made cave, transforms into new cultural and tourism landmark

By Liu Xinyu

(ECNS) – With the recent surge in popularity of the "503 Geocentric Roaming Loop" in Fuling District of Chongqing, the 816 Project Scenic Area -- the world's largest man-made cave structure -- has drawn a large number of domestic and overseas tourists, with its attractions enhanced by sound, light and electrical technologies.

Construction of the 816 Project began in 1966. More than 60,000 builders participated in the project. The total excavated area exceeds 104,000 square meters. The cave complex contains 18 large caverns and more than 130 tunnels, branch caves and vertical shafts. The main cavern, standing 79.6 meters high with 12 floors, is entirely hidden inside the mountain and is known as the "world's largest man-made cave."

The lighting system uses LED projection and laser mapping technology to enhance the technological atmosphere while preserving the original appearance of the project, allowing visitors to experience the mystery of this "underground Great Wall."

Stepping into the cave, visitors are greeted by a visual spectacle where light and shadow intertwine with the industrial texture of the space. Giant projection screens on the rock walls display futuristic cyberpunk imagery. In the core areas, shifting lights create a futuristic atmosphere.

In recent years, local authorities have leveraged the site's unique historical and spatial resources through preservation, utilization and integration of culture and tourism, bringing this underground nuclear facility into the public eye and attracting a growing number of visitors from across the country and around the world.