Giant Rock, California

Several people are known to have lived in a cavity underneath this giant rock, hollowed out by German immigrant miner Fritz Critzer in the 1930's. Critzer managed to live unmolested in his rock abode until the advent of World War II, when suspicions arose that he was a German spy, due in part to his having positioned a radio antenna nearby. In 1942, during the course of a police raid, Critzer was killed when a tear gas grenade ignited a case of dynamite, which he had kept on hand for use while prospecting out in the desert. Five years later, a former test pilot and UFO abductee, George Van Tassel, moved his family into the rock, and the location became known as a site of major UFO activity (Van Tassel built the Integratron energy machine three miles south of the Rock). Popular UFO conventions and events were held here until the 1970's.  Located north of Landers, it became a popular rave location in the 1980's and 1990's, attracting as many as 3,000 partiers. On February 21, 2000, a huge piece of the rock split off, to reveal a white granite interior, while nearly crushing an RV in the process. Some say the break occurred due to the heat from a bonfire that burned next to the rock the night before. Others have proposed more metaphysical explanations. There are also those who maintain that Giant Rock is the "largest free-standing boulder in the world," although the veracity of that claim is unclear.