Secret Tunnels Under the USA?

I’ve always liked the idea of secret underground cities for some reason. I imagine all the reasonable people live down there and they leave all the nuts on the surface. Dennis Balthaser has an interesting article up on the UFO Chronicles about government secrecy containing a link to one of the biggest tunnel boring machines I’ve seen yet:

The United States has a variety of underground tunnel systems, including old and forgotten tunnels, as well as those used for transportation, business, and government purposes. These tunnels are found in various states and serve different functions. Some examples include the Subtropolis Business Complex in Kansas City, which is claimed to be the world’s largest underground business complex, and the extensive tunnel network created during the Cold War for government and military purposes. Additionally, there are abandoned tunnels and mines, such as those created during the Gold Rush in California. While the existence of these tunnel systems is well-documented, the extent of any secret tunnels connecting different states is not definitively known. However, there are historical and contemporary references to the existence of secret underground facilities built by the U.S. government, particularly during the Cold War[1][2][3].

The search results provide information about various underground tunnel systems in the United States, including those used for business, government, and military purposes, as well as abandoned tunnels and mines. While there are references to the existence of secret underground facilities built by the U.S. government, the specific details and extent of any secret tunnels connecting different states are not clearly outlined. Therefore, it can be concluded that the existence of many secret tunnels under the USA, connecting different states, is not definitively confirmed.

Citations:

^{[1] https://www.groundworks.com/resources/u-s-cities-with-incredible-underground-tunnel-systems/
[2] https://youtube.com/watch?v=IKuhF5zFT1M&t=1097
[3] https://www.theringer.com/movies/2019/3/27/18283803/us-tunnels-truth
[4] https://www.atlasobscura.com/lists/7-tunnels-under-government-buildings
[5] https://spyscape.com/article/10-secret-cities-that-were-hidden-from-prying-eyes}