Hopi legends were said to describe a race of "Lizard" people who, 5,000 years ago, built three great underground cities near the Pacific Coast, including one beneath Los Angeles. In 1934, mining engineer W. Warren Shufeld took up the cause of researching these legends and locating the cities. Shufeld reported that the city beneath Los Angeles was laid out in the shape of a lizard that extened from Dodger Stadium to the downtown Central Library. It was built used chemicals to tunnel through rock. The civilization came to an end due to meteors or fire. Using a device Shufeld called a "radio X-ray," he claimed to have located tunnels and a treasure room beneath Fort Moore Hill in downtown Los Angeles. After acquiring funds to do some excavating, Shufeld obtained permission from the authorities to drill a 350-foot shaft. The work was interrupted by cave-in concerns and, shortly thereafter, Shufelt disappeared from public view. Just prior to the drilling, Pico Rivera resident and psychic Edith Elden Robinson reported a vision of "a vast city...in mammoth tunnels extending to the seashore."
Source: Mysterious California by Mike Marinacci; Panpipes Press