Hyundo Ahn, a 25-year-old South Korean exchange student who had just completed a year at the University of California/Davis, obtained a wilderness permit for an ambitious eleven-day hike on the John Muir Trail from Yosemite Valley to Mount Whitney on June 20th. After the hike, Ahn planned to visit several other sites in the U.S. and had tickets for his return flight to Korea for July 21st. He apparently started the hike on June 21st, but changed his route due to the late lingering snow pack in the Sierra. On July 21st, the park was notified by the Davis police department that Ahn had missed his flight home. Intensive investigation, including several hundred telephone calls to wilderness permit holders by volunteers, led to backcountry witnesses who had spoken with Ahn on June 22nd and 25th. The areas identified from these clues were intensively searched by helicopter, ground searchers and dogs. When Ahn was not found, the search was scaled back after the weekend of July 30th. Through the following week, limited field searching continued. On Friday, August 5th, a single search team was traversing Tenaya Canyon, an area that had not been previously ground searched, when they found Ahn's backpack on the bank of Tenaya Creek. The next day the area downstream from the pack was searched. Ahn's body was found about a mile downstream from the pack. It appeared that Ahn had fallen in the creek, swollen by spring runoff, and had been underwater until the creek receded. Ahn's body was flown from the remote canyon by the park's fire management helicopter. An autopsy found that his death was caused by multiple blunt force injuries. A journal and digital camera found at the scene lead to the conclusion that Ahn died sometime midday on June 26th.