A complex network of passages, intersections, chambers, and underground water accumulations was built beneath the Bosnian Pyramid of the Sun. The discovery of this labyrinth was announced by the discoverer of the Bosnian pyramids, Dr. Semir Osmanagic, in his book in 2005, basing his hypothesis on similar examples of underground tunnels in Egypt, China, and Mexico. Until then, it was believed that the low entrance and fifty-meter tunnel passage in Visoko was a “natural cave”. There are no negative radiations in the labyrinth: cosmic (Hartmann, Curry, and Schneider grids), natural radioactivity, or negative energy from underground water flows. Therefore, this location is one of the safest on the planet and allows for the protection of health and body revitalization. The Foundation’s activity involves cleaning the existing prehistoric tunnels from the brought-in gravelly material and securing them with wooden underlay of tunnel passages that lead towards the Bosnian Pyramid of the Sun (southeast direction). The air circulation is excellent and achieved through the different height of the ceilings, causing different pressure and natural ventilation. The slope of the tunnel is 1.5 degrees, which enables fine water drainage. The concentration of negative ions, which cleanse the atmosphere from bacteria and viruses, is several tens higher than the average, which explains the beneficial effect of the tunnel on the human body.