Project 816: Touring the World’s Largest Underground Nuclear Maze
Project 816 Highlights
Deep in Chongqing’s Fuling District, nestled at the base of the Great Rift Valley near the quiet town of Baitao, lies a hidden marvel that defies imagination: Project 816.
This sprawling underground complex, once a top-secret nuclear weapons facility, is the world’s largest known man-made tunnel structure and China’s only publicly revealed military nuclear site. For decades, it remained cloaked in secrecy—its existence unknown to the world, its workers vanished, and its hometown erased from maps.
The story of Project 816 begins in 1984, when approximately 60,000 workers were secretly hired to carve out a labyrinthine fortress. The nearby town of Baitao was mysteriously wiped from Chinese national maps for 20 years, and many of its workers seemingly disappeared. The facility wasn’t revealed to the world until 2002, and in 2010, it opened its doors to the public as a tourist attraction.
The facility was never operational, making it safe for tourists to visit, with no risk of radiation exposure.
Getting There
Driving
Driving is recommended to visit this place.
Parking
Paid parking is available at this location.
Parking is only available at the designated parking lot. Please navigate to 816 游客中心.
Things to Do
Viewing
Enjoy this military megaproject with a surface area of more than 104,000 square meters inside the cave.
Facilities
Accessibility
The entrance leading to the first couple of rooms is on a concrete flat road with partial accessibility.
Lots of stairs are involved in this experience.
Not recommended for people with mobility issues.
Cell Service
Limited cell service is available at certain locations.
Restroom
Restrooms are available at limited locations.