in 1984. A rainstorm caused a crack in 1989 which caused it to collapse. Knight was not discouraged; he rather saw it as God's way of letting him know the Mountain was not safe. He began work on the current Salvation Mountain "with more smarts" – such as better materials and engineering, including adobe mixed with straw. After completion, the "mountain" was several stories high and was about a hundred yards wide. In 1998, Knight wanted to expand the mountain. He gathered ideas from the Navajo who settled in the area around Salvation Mountain. Their pueblitos inspired Knight and he then began forming the Hogan. It is a dome-like structure made of adobe and straw that insulates from heat. Knight intended to live in it, though he always preferred to live in a shack on the back of his truck, and did so for 27 years. For a long period, he had help with the project from a friend, Bill Ammon ("Builder Bill"), of Slab City. Knight was known for giving free tours to every visitor at Salvation Mountain. An article about Leonard Knight stated that he was a "visionary American folk artist" whose message was "unconditional love to humankind". Knight "arrived accidentally ... [but] immediately recognized an opportunity to continue his large-scale gospel message. He made a mountain with his bare hands. Leonard built Salvation Mountain". Later years Knight also began another formation, what he liked to call "the museum". It is modeled after the semi-inflated hot air balloon Knight tried to create before Salvation Mountain; the balloon is now on view at the American Visionary Art Museum. The museum is a semi-dome structure in the mountain that contains several small items given to him by friends and visitors. Each item has a significance and, more often than not, visitors seek out Salvation Mountain to pray and leave an item at the mountain as symbolism of giving themselves to God. The museum is held up by adobe and straw, but also by car parts and a tangle of trees that twist within the dome and reach through the top. Over the last ten years of his life, Knight planned to repaint the mountain twice a year to ensure that the paint layer would be very thick. He was unable to continue this because of an injury sustained in 2011. Afterwards, a public charity, Salvation Mountain, Inc., was established to