george van tassel started hosting group meditation in 1953 in a room underneath giant rock excavated by frank critzer. that year, according to van tassel the occupant of a space ship from the planet venus woke him up, invited him on board his space ship, and both verbally and telepathically gave him a technique for rejuvenating the human body. in 1954, van tassel and others began building what they called the "integratron" to perform the rejuvenation. according to van tassel, the integratron was to be a structure for scientific research into time, anti-gravity and at extending human life, built partially upon the research of nikola tesla and georges lakhovsky. van tassel described the integratron as being created for scientific and spiritual research with the aim to recharge and rejuvenate people's cells, "a time machine for basic research on rejuvenation, anti-gravity and time travel". the domed wood structure has a rotating metal apparatus on the outside he called an "electrostatic dirod". van tassel claimed it was made of non-ferromagnetic materials: wood, concrete, glass, and fibreglass, lacking even metal screws or nails. the integratron was never fully completed due to van tassel's sudden death a few weeks before the official opening. in recent times some people who visit the unfinished integratron claim to be rejuvenated by staying there, and experiencing "sound baths" inside.