George Van Tassel, creator of the Integratron, was a legendary figure, an aeronautical engineer and test pilot who worked for Lockheed, Douglas Aircraft and alongside Howard Hughes at Hughes Aviation . He was also one of the leaders in the UFO movement who held annual "Spacecraft Conventions" at Giant Rock for 25 years. Van Tassel said UFO channelings and ideas from scientists such as Nikola Tesla led to the unique architecture of the Integratron. He spent 18 years constructing the building.

In 1947, after an exemplary career in aviation, Van Tassel moved his family to Giant Rock in the Mojave Desert near Landers, California and opened Giant Rock Airport and a cafe called The Come On Inn. He leased four square miles of land from the government, including Giant Rock, a 7-story high, freestanding boulder formerly sacred to the Native Americans who lived in the area.   

Van Tassel learned of Giant Rock from Frank Critzer, a prospector and desert dweller, who had excavated under the massive boulder to construct a dwelling of several small rooms protected from the fierce sun. Critzer had been killed in a explosion of the dynamite he kept stored in his rooms, the circumstances of which are still a mystery. The gutted rooms became storage for the Van Tassel family, but they slept outside the Rock and during the day tended the airport and their small cafe.

George Van Tassel began conducting weekly meditation sessions in 1953 in the rooms underneath Giant Rock which, he claimed, led to UFO contacts and finally to an actual encounter with extra-terrestrials when, in August of that year, a saucer landed from the plant Venus, woke Van Tassel up and invited him onto the ship. There the aliens gave him the technique for rejuvenating living cell tissues. In 1954 he and his family began building a structure they called The Integratron to perform the rejuvenation. George described his creation this way, "The Integratron is a machine, a high-voltage electrostatic generator that would supply a broad range of frequencies to recharge the cell structure."

His annual Spacecraft Conventions were attended by tens of thousands across two decades, featuring speakers that included high profile UFO contactees and pioneers in the fields of antigravity, primary energy research and electromagnetics. Van Tassel led weekly meditations in the rooms under the rock from the 1950's to the 1970's, which he claimed led to UFO contacts.

The family hosted their UFO conventions at Giant Rock for almost 20 years to raise money for the Integratron project and asked supporters for donations. In 1959, 11,000 people attended the spacecraft convention, and Van Tassel continued to work on the Integratron while writing a number of books on time travel and rejuvenation. Van Tassel died suddenly in 1978, after which the buildings at Giant Rock were vacated and gradually vandalized until the Bureau of Land Management found it necesary to bulldoze the remains.