Yes, governments around the world, including the United States, have built underground facilities for a variety of purposes, such as military, scientific, and storage facilities. These facilities can be located deep underground, and some are even designed to withstand nuclear blasts or other catastrophic events. Some of these facilities are publicly known and documented, while others are classified and kept secret.
Where is the largest underground facility?
It is difficult to determine the largest underground facility as many of them are classified and their exact sizes are not publicly known. However, there are some well-known large underground facilities such as The Gotthard Base Tunnel in Switzerland, which is the longest railway tunnel in the world, stretching over 57 km (35 miles) underground. The Oresund Tunnel, which connects Denmark and Sweden, is 7.8 km (4.8 miles) long and includes an artificial island. The Shanghai Tunnels, a vast network of tunnels located underneath the city of Shanghai, China, are believed to be several hundred kilometers long. It's worth noting that there may be larger underground facilities that are not publicly known or have not been disclosed.
John Vaiea AI