Underground bases
Underground bases is the umbrella category for subterranean installations treated in exopolitics and conspiracy theory literature, covering modern classified military facilities, alleged extraterrestrial or non-human-occupied complexes, ancient tunnel systems attributed to pre-flood civilizations, and the Agarthan network of claimed deep-interior settlements. Estimates of scale range from the hundreds of documented U.S. installations identified by Richard Sauder to the thousands of globally connected facilities claimed by Phil Schneider.
Categories
Deep underground military bases
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Deep underground military base
Classified installations typically constructed 1,000 feet or more below the surface using tunnel boring machines, controlled blasting, or alleged nuclear-powered subterrenes. Public examples include the Cheyenne Mountain Complex, Raven Rock Mountain Complex, and Mount Weather; alleged black-budget facilities include Dulce Base, Area 51 underground levels, the Manzano Base, and the Peters Mountain complex.
Ancient tunnel systems
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Ancient tunnel systems
Pre-flood subterranean networks reportedly repurposed by modern military programs, including the passages beneath the Giza pyramid complex, the Derinkuyu underground city in Cappadocia, the Longyou Caves, and alleged labyrinths connecting Cusco to the Sacred Valley. Gene Decode characterizes Earth as "a giant honeycomb" of ancient tunnels continuously expanded by successive civilizations.
Agarthan network
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Agarthan network
Alleged deep-interior civilization with installations at Telos (beneath Mount Shasta), Shambhala, Agartha, and other locations connected by a planet-wide tunnel system. Treated in Theosophical, Lemurian, and contemporary exopolitics traditions as a surviving pre-cataclysm human or post-human population.
Subterranean cities
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Subterranean cities
Large-scale underground population centers, alleged both as historical remnants (Derinkuyu, Cappadocia, Bosnian tunnels) and as contemporary occupied facilities of up to city-scale capacity. Phil Schneider described the Area 51 complex as "nine separate underground bases... basically a city underground, roughly four and a quarter cubic miles hollowed out."
Undersea installations
Permanent manned sub-seafloor facilities, proposed in a 1966 U.S. Navy document titled Manned Undersea Structures — The Rock-Site Concept (NOTS TP 4162, Naval Ordnance Test Station, China Lake) and allegedly realized at sites including AUTEC on Andros Island.
Global scale and connectivity
Alleged planet-wide connectivity is a recurring feature of the literature. Richard Sauder documented declassified RAND, Army Corps of Engineers, and Defense Nuclear Agency planning studies proposing networks of installations up to 4,000 feet deep across the continental United States. Catherine Austin Fitts estimated approximately 170 underground facilities in the U.S. alone, financed by what she describes as a "secret book" mechanism routing $21 trillion in undocumented federal adjustments through the Bank for International Settlements. Installations are allegedly connected by high-speed magnetic-levitation shuttles in vacuum tunnels, based on a 1972 RAND study by Robert Salter describing speeds of up to 14,000 mph.
NHI occupation
Approximately half of the 131 U.S. deep underground military bases claimed by Schneider are alleged to function as "cities for them" — the non-human intelligent beings — rather than for human military use. Thomas Edwin Castello's description of Dulce Base described seven sub-levels containing Grey and reptilian personnel, genetics laboratories, and holding cells. According to Elena Danaan, four principal underground headquarters coordinate NHI operations worldwide: beneath Dulce Base, off the coast of the Bermuda Triangle, off the coast of Denmark, and off the coast of New Zealand.